Thank you @HCP for your answer. I understand better the code to pu tin the console.
That *might* explain the differences if the first wallet was showing mBTC while Electrum was showing BTC and you've just missed a 0 and the balances are actually 0.38 mBTC and 0.0004 BTC
In fact no, the settings were ok.
https://snipboard.io/xj9bAD.jpgFollowing your advice and BRD suggestions, I let the BRD wallet sync in slow mode and made a transaction. Then I tried to understand the gap between balance by analyzing csv files. In BRD Fast sync, 4 transactions are missing.
I tried to verify with block but for one address, I have many transactions that don't match my csv files.
I am gonna send all these csv files to BRD support.
My question is: is it possible that I lost BTC during a fork or BCH creation?