I wonder if there is any DEX that is safe and allows Derivatives or Future trading with a good leverage?

I guess not.
At least with good liquidity.
But happy to be proven wrong on this.
CEX are too good for the moment for DEX to really pick up.
Maybe with a tightening of KYC/AML constraint we will see dex rise..
Since we are here:
I am less active on the forum for a reason:

This is a secret location.
I decided to use the compulsory WO hand sign, as the classic Italian stallion sign is less known: