-What GPU is best suited to the monero like coins?
Vega or rx580
-Does the XMR-stack app support multi GPU rig? If yes, it uses them automatically/ If not, what mining hardware do you recommend?
yup
- Which pool do you recommend for multi-GPU rig (i think crypto-knight is fine), i am based in france.
I use this one
https://xhv.luckypool.io