Very cool find here: Ender 3 V2 Schematic for 4.2.2 board · Discussion #814 · Jyers/Marlin · GitHub
PDFs also attached here for reference
Creality.4.2.2.-.Schematic.28-5-22.pdf (188.1 KB)
Creality.4.2.7.-.Schematic.28-5-22-1.pdf (193.7 KB)
In addition the 4.2.2 board apparently can come with different driver chips:
Creality V4.2.X Board Driver Codes
The letters written on the card reader slot (with marker) are different depending on which stepper driver it has.
These are for the ones 4.2.X board with STM32F103RET6 controller:
C = HR4988
E = A4988
A = TMC2208
B = TMC2209
H = TMC2225
Credits to the folks in the above link. Must have been an insane work to establish these schematics. 