Thank you both for your answers. @lukasmaximus is right I would prefer using the standard micropython firmware. As I wasn't able to find an available python module I took a look at the M5StickC Arduino code (https://github.com/m5stack/M5StickC/edit/master/src/AXP192.cpp) and transferred the parts I needed to python. The available datasheet is just in Chinese but together with the code I got the display enabled.
Here is my prototype code to enable the display and backlight. Please be aware that I haven't included everything from the cpp file so some functionality is missing:
from machine import I2C
i2c = I2C(freq=400000, sda=21, scl=22) #Enable I2C
i2c.scan() #Check for devices
[52, 81, 104] #52 is the adress of AXP192
i2c.writeto_mem(52, 0x28, b'\xcc') #Set TFT and TFT_LED to 3.0V
i2c.readfrom_mem(52, 0x12, 1) #Read Byte 12
#returns b'\x13' = 0b10011 -> DCDC enabled but LDO3/2 disabled
i2c.writeto_mem(52, 0x12, b'\x1f') # enable LDO3/2 (TFT and TFT_LED)
# other code parts:
i2c.writeto_mem(52, 0x12, b'\x13') #disable LDO3/2 (TFT and TFT_LED)
i2c.writeto_mem(52, 0x28, b'\x9c') #Dimm display by reducing the voltage
One important thing is that the register 0x12 is also responsible for powering the ESP32. Thats the reason why just setting the LDO3/2 bits alone isn't enough.