Mortar Max supports RGB color mode.
Mortar Max supports RGB color mode.
It seems you're looking for a USB to ARGB hub similar to one from coolermaster. There doesn't appear to be any compact USB to 1x or 2x ARGB headers available right now. It might be possible to manage ARGB devices using an Arduino's GPIO header if you have the programming skills, though buying a dedicated hub could be more convenient.
You might attempt this approach, but it could cause argb fans to behave like rgb fans on a 12V MB header. Otherwise, you'll require a USB 2.0 controller or a manual controller. Edited June 9, 2021 by thrasher_565