Event tick hooked to a line trace and only one "cast to actor" node make my fps fall slowly to unplayable. Is there any alternative to fix this ?

[Everynone]

This is will crash & burn at some point once accessed and evaluated in another execution chain:

If you need this data elsewhere, do the trace there to obtain it. Or store a ref to the hit actor and use it after checking its validity. Tracing is very cheap, casting is more than OK and Tick is necessary. What’s expensive is using it incorrectly.