there should be a checkbox like Add Electrum-style address type prefix. Electrum would add prefixes like "p2wpkh:" and "p2sh-p2wpkh:" to WIF private keys, to distinguish between different address types.
Such incompatible WIF was at least controversial, so that even Electrum itself had deprecated it. I didn't anticipate this would happen. To be frank, this was disappointing for me.
This was originally suggested in #373:
Probably this has not even been documented, I could just find this description in the code: https://github.com/spesmilo/electrum/blob/787ac5fe994086b994524201fec4b63f876c7c85/electrum/gui/qt/installwizard.py#L41
BTW, Electrum had once used an incompatible WIF, too: https://github.com/spesmilo/electrum/blob/787ac5fe994086b994524201fec4b63f876c7c85/RELEASE-NOTES#L462
Such incompatible WIF was at least controversial, so that even Electrum itself had deprecated it. I didn't anticipate this would happen. To be frank, this was disappointing for me.
So far, according to answers to this question, in the future, output descriptors might become the new standard.