Is it recommended to generate a new seed after importing funds (with the help of the 12 word phrase from BRD wallet)
to Electurm?
Importing a seed phrase only "copies" the private keys from the original wallet (BRD) to Electrum.
Since both Electrum and BRD wallet both has a copy your private keys now, either wallet can spend your coins.
If you do not want the previous wallet to have access to your funds, then you should send 'max' to a new Electrum wallet with a new seed.
If you still want to access it in BRD wallet, then keep it that way. (your transactions will reflect on both wallets)
The same, if funds from a paper wallet are sweeped to Electrum?
If you think about it, this is a reckless question since sweep requires an existing Electrum wallet (that you own),
it does not create a new wallet from the paper wallet so there's no reason to ask if it's necessary to create a new seed.
If you're talking about "import private key" instead, then it's recommended to create a new wallet if you're not planning to spend it all right away.
P.S.: It would be nice if you can reply to your topics to report that your queries are already answered, at least for closure purposes.
I peeked into your post history and only a few older topics have reply.