The Womier RD75 Pro is a clone of the PMO WAVE75. Therefore the firmware of the RD75 is comaptible with the firmware of the WAVE75 and vice versa. If you use the firmware of one model, you must also use the related VIA JSON config file.

In the downloads section you can find

• Original firmware for the PMO WAVE75 keyboard
• The VIA JSON file that contains the default keyboard definition
• The User manual (PDF)