Voltlog has a programmer for the ESP32 that I thought looked nice. ( https://www.tindie.com/products/voltlog/voltlink-cp2102n-usb-serial-adapter-programmer/ )

But I do not like to run it powered and not protected so I made this small case.

I made the hole for the pin header large enough so a 6 pin DuPont connector should fit.

Depending on how precise you printer is some post processing might be needed.

I use m2.5 12mm long screws... that acts as feets also... 11mm would be prefect...