that cute little face is made out of two simple geometries. Both are printed with the same Firmware BUT the left one with CoreXY enabled and the other one with X/Y resolution * sqrt(2) to fix the scaling.
Although the infill seems problematic on the right one it is the left one that makes problems. It is not round!!!
Here’s another picture, this times right one is coreXY enabled:
You can see a flat part right from the top of the right part while the other part doesn’t show any bigger problems. To be exact you can see the inset, that’s it. That’s the biggest issue with coreXY in Marlin for me, exept homing y wich is just a little ugly.
I will use normal tweaked firmware until it is fixed.