I would like to create a BIP39 24 word seed for holding.
Is Sparrow Wallet trusted for such task? I'm planning on doing it on an
offline PC without ethernet cable and booting Linux from a USB installation disk (Example:"Try Ubuntu before Install" option). And then following these steps:
https://sparrowwallet.com/docs/quick-start.html#creating-your-first-walletOnce the seed phrase is generated I'll backup and import it into an air-gapped hardware wallet.
I would advocate hardware wallet as a SEED source. At least with such opt you could be able to use multisig set up grounded on Sparrow and your air-gapped HW. Here you can find instance relevant to Passport-Sparrow-multisig wallet.
Even offline computers (being infected ) may create compromised SEED.