i made a bech32 key with vanitysearch and imported the wif into bitcoin-qt 0.18.0 but it ends up giving me the old style with the 1 prefix. i have bech32 enabled as default in the options; if i let the wallet generate a random key for me it is bech32. so how to import a key as bech32 ?
you must import the private key full like "p2wpkh-p2sh:5priv.key" or "p2wpkh:5priv.key"
AFAIK this will only work with Electrum.
Have you tried this prefix method with Bitcoin-qt or Bitcoin Core?