My Mainboard only supports one CPU and case fan at a time, which isn't enough I figured out today. Fan splitters are apparently a thing, tho you can't manually adjust them when connecting in return right? I'm planning on buying two Corsair RGB fans soon, so would I still be able to adjust their colors using icue after connecting them with the splitter?

The Corsair RGB Fan LED Hub is also a thing: https://www.corsair.com/de/de/Kategorien/Produkte/Custom-Cooling/Zubeh%C3%B6r/CORSAIR-RGB-Fan-LED-Hub/p/CO-8950020

I'm not quite able to tell what it exactly does tho. Is this already a splitter in itself or do the fans need to be connected inside here AND on the Mainboard in order to adjust them?

I hope you were able to understand everything properly and really appreciate your help.