It’s possible to crop in our Android app, but not our iOS app. You can see this annoucement for the future of the iNat mobile app. I can’t promise a cropping tool in it, but I’d be surprised if there wasn’t one - for photos taken within the app it especially makes a lot of sense. I think it’d be great to add a cropping tool to the web uploader, but as there are free cropping tools for desktop/laptop computers, it’s not a high priority.
Seek by iNaturalist does suggest cropping a photo if it can’t get a confident CV ID for it. I could see that eventually being added as some sort of onboarding in the future for the standard iNat app.
As to whether a cropping tool would help with either training the CV* model or getting accurate results from a submitted photo for taxa like this, I’m not sure.
*We try to use “computer vision” rather than AI because it’s more accurate - our model isn’t really artificial intelligence)