I’ve successfully wrote a BMW EWS3 PCF7935 transponder key with xhorse tools no soldering.
Device used:
Xhorse XDNP50 BMW EWS3 Adapter for Mini prog/key tool plus (it is different from EWS3 adapter for vvdi prog)
VVDI super chip and key shell
Step 1: Read eeprom with mini prog
Connect EWS3 adapter with mini prog, read and save dump
Step 2: Write key pcf7935 with key tool max