Battery warning light

Kenny thanks for your patience and response. I have already identified the part and it will be an easy install. I will give an update here after I try adding more drive cycles and then a reset.
The reason I want to try more drive cycles is because in the link given earlier the article said that:
"in some vehicles, if the sensor has been disconnected or the battery has been replaced, the Stop-Start feature might not work for some time, until the computer (BCM or PCM) re-learns the parameters of the battery."
In my case I had about 5 years old OEM EFB battery and the battery warning light came on and I replaced it with not an EFB but with an AGM, hence maybe the system is taking time.
This article also says what Kenny you said earlier that scan is better than resistance measurement.
"Some require measuring the resistance between the sensor pins, others advise using a scan tool to test the sensor. "
Since I do not have a scanner (other than self-diagnosis report which did not show the current sensor DTC), I will remove current sensor and -ve terminal, clean and make sure it is dirt free not just visual but by air/dust remover similar to PC circuit board cleaning. If this does not work, then definitely a new part.

Some times I like to repeat what I say earlier because we all are busy and not as close like the person who is facing the issue. I will definitely update the outcome here.
Yes, first time I got battery warning light on Jan 1, it was raining and car was parked outside garage. I completed an errand/a short ride.
I started battery search on Jan 2, found out original OEM battery was discontinued by Nissan and the replacement battery with different part # 999M1-NBH5A in my area was backordered with dealers. I guessed it is Group H5 from part #. Nissan has not published specs like dimensions and CCA on this. During my work travel in AL, stopped by at a dealer and got the sizes measured and it was 600 CCA. It indeed is Group H5 (BCI 47) so bought this and replaced.
When I got battery warning I examined the terminals and connections all were clean, checked relevant fuses and measured V with and without load. Also got it tested at neighborhood Advance Auto store, everything passed but low CCA, so put it on a trickle charger, drove for a week and again everything passed except lower CCA. So with peak of Winter and low temps here in Northeast decided and replaced with AGM Battery. This is the first Carwhich consumed lot of time for finding appropriate Battery as even Interstate site does not show replacement battery available for 2017 Nissan Rogue Sport or QashQai. So I went by group/BCI and replaced with H5(47) AGM battery it worked. Except the Battery Warning light is still lingering. Then I thought because it is Europe model rebranded for USA may be I have to establish or register, but dealer does not know, although some Nissan dealers mention establishing or registering Battery using Nissan Consult computer. The Nissan dealer I went to wanted to solve it by trial and error by first replacing Alternator, then may be something else and then may be ECM. All I asked the dealer, what assurance can he give me that with Alternator Battery light warning will go away and he could not. I know that there is nothing wrong except may be Current sensor or something simple communication or ECM itself can be bad (based on Nissan Rogue/Infiniti forum).
So long story short, to answer you, it did not start after putting AGM battery. I checked with another person in Nissan forum, in TX region, he replaced OEM EFB with another EFB and no warning light before or after. In his case battery was dead before replacing and no battery warning light for old battery.
Costco where I bought battery had only AGM another far away Costco had H5 EFB and I wonder, if I were to replace with EFB would the battery light gone. Well, this is a great learning experience for me.

And you do confirm no battery registration required after replacement (like in BMW or VW)?

I appreciate the confirmation. It is better to confirm than realize later that key FOB or some hard programmed memory got wiped off! Or radio got locked out or needs an unlock code.

Update: could not remove negative terminal nut after leaving it sprayed with WD40. Will try different penetrating oil/solvent which will not attack plastic part, maybe the nut is fixed using some thread sealant. No major rust noticed. Cleaned still Battery light on.
To replace with new part if nut doesn't come loose will cut wire and use another crimped copper terminal end, looks like there is some slack in wire so it will not be short.
Questions:
1. This wire could be bolted to chassis and underneath the triangle shaped fuse box?
2. Please see attached self-diagnostic report attached again, can you point where CHG/Battery current sensor may be listed as error? Or it does not have to be and captured under something else?

Perfect! And this completes the circle! My original post said that I tried to convince dealer that since alternator is without fault, based on U1040 which is first DTC on the report and it has 3 different reasons in general based on general web search and they all point to faulty ECM. So if ECM is faulty what good a new alternator would do?
Dealer is trying to explain me that Nissan troubleshooting says first replace alternator and then ECM (or in my opinion dealer may say something else say starter, current sensor and then ECM). This is all "trial and error" solving the issue of Battery light warning!
This is one of the reason I still feel that ECM does not register that there is not an EFB but AGM battery. I still wonder what if I were to replace EFB with an EFB, would battery light would have gone by itself? I don't have a back up EFB or another vehicle that will allow me to test this hypotheses.
I still feel ECM (assuming it communicates properly and is without fault) continuously monitors and write new information so after certain number of drive cycles will overwrite new AGM battery parameter (or give up displaying battery error light). (May be a wishful thinking!)
In UK some users of QashQai have faced that by replacing horn fuse under hood of 15 amp the light went away. Since the car horn is working, I do not think it is the case here.
That leaves now resetting ECM (by certain sequence of accelerator pedal pressing). I spent morning looking for low cost OBD II scanner which allows Battery charging analysis, real time preferably! Haven't found one. Cannot afford Consult III system.
Coming back to U1040 and U1044:
(a) continuity exists in harness (please see attached)
(b) in absence of hi-tech tools that wipes DTC, do you think resetting ECM (by acc pedal sequences) would clear up Battery warning light?

(c) Based on self diagnosis at CRNT=current time
Nissan Codes on Jan 20, 2022 (at CRNT=current time during diagnostics) this is what I understand that ECM is the issue here.
U1040 NISSAN code possible causes
†Faulty Engine Control Module (ECM)
†Engine Control Module (ECM) harness is open or shorted
†Engine Control Module (ECM) circuit poor electrical connection
U1044 NISSAN code possible causes
†Faulty Generator
†Generator harness is open or shorted
†Generator circuit poor electrical connection
U1051 NISSAN code possible causes
†Faulty Generator
†Generator harness is open or shorted
†Generator circuit poor electrical connection
†Faulty Engine Control Module (ECM)
Please inform, and thanks for all your help. Also no OBD II codes at a store (see attached photo)

Do you think unplugging ECM harness and re-plugging can clear out this error?