To reply to myself to the second point
“Secondly, I’m trying to use EssentialMode4 and es_rp. I have to change all couchDB requests for mysql-async requests or the king Brouznouf handles all the couchDB requests in his resource ?”
We just have to use this code provided by @Kanersps : [Release] EssentialMode base - #1181 by Kanersps