Does a set of private keys have a different XPUB and ZPUB for single signature and multisig?

Question

I am experimenting with multisig wallets using Sparrow. I have two Nano Ledger hardware wallets each set up for single signature with different private keys. I used them to create a 2 of 2 multisig wallet. I was expecting the XPUB and ZPUB for each individual keystore to be the same as those in the single signature wallets for the same device. However, the XPUB and ZPUB were different.

Does a set of private keys derive a different XPUB and ZPUB depending on whether it is being used as a single signature wallet or whether it is joining a multisig wallet setup?

If so, do the XPUB and ZPUB change depending on the signature of the multisig wallet? e.g. would the XPUB and ZPUB for each device change again if they were added say to a 2 of 3 or a 3 of 3 or a 3 of 5 multisig wallet?

Answer 1

Does a set of private keys derive a different XPUB and ZPUB depending on whether it is being used as a single signature wallet or whether it is joining a multisig wallet setup?

Yes, because the derivation paths are different. Most wallets use m/48'/0'/0'/2' for multisig, but m/84'/0'/0' for single sig.

If so, do the XPUB and ZPUB change depending on the signature of the multisig wallet? e.g. would the XPUB and ZPUB for each device change again if they were added say to a 2 of 3 or a 3 of 3 or a 3 of 5 multisig wallet?

No, the xpub would not change if the same derivation path is used (and the multisig qorum, i.e 2 of 3, etc is not related to the derivation path).