Ah. As often happens, making the topic helped me to figure it out already.
1 divided by the delta time from Tick and connect Tick to float variable “Current FPS”. Then I have the Current FPS making the branches whether extra effects are made.
This does add 1 more constantly ticking variable change and a divination to the blueprint, which uses resources itself though. Doing the checks once per second etc. would be good enough, but for FPS checking the variable must correctly ticked to the frames to work.