I see! I guess the problem is the lens or the lens adapter...
You weren’t clear as to what equipment you’re using. If you’re using a legacy lens
w/ Canon’s own EF/RF adapter on the R5 , check your manual because there may indeed be a [AF Micro Adjust] menu option. If there is, this would ONLY be applicable to adapted lenses on Canon's proprietary adapter.
It is more likely, with an adapted lens, you’re seeing focus shift as the Canon focuses wide open and stops down at the moment of capture. This would be a function of lens firmware not your R5.
Finally, IIRC, Canon has settings under [lens aberration correction] , digital lens optimiser should be disabled w/ adapted lenses.
Edit:
If you're using
3rd party lenses and/or adapters - manual focus if problems persist.