It's maybe worth mentioning why it's not possible to import a WIF private key into Sparrow (I'm not yet convinced it's not possible, see below) and in some cases also not in Electrum.

If a wallet already exists, newer ones are usually a HD wallet. You can't import an unrelated private key to such a HD wallet, because the unrelated private key won't be backed up by the wallet's mnemonic recovery words.

This is the reason why e.g. you can't import a WIF key to an already created Electrum HD wallet. You can only sweep a WIF key in such cases.


I haven't tried myself yet, but I think it should be possible to import a wallet based on descriptors in Sparrow. You would have to convert your WIF private key to a descriptor and the open question remains, if Sparrow accepts such single private key descriptors. I wil have to check this later when I find time for it.