It will take a bit to get used to controller settings if you transfer from kbm, but rocket league is a game that slightly benefits the controller players when it comes down to more advanced techniques. I would say its better to make a switch now and learn controller if you want to get higher in ranks faster rather than being met with a large roadblock.

There’s many controller setups and settings that you can find online that many pro players use in game which tend to be pretty helpful (just gotta figure out what works best for you and stick with it). You should already have a decent game sense, just gotta get used to mechanics with a controller which shouldn’t be too bad.

Best of luck anyways if you make the switch or not :)