I know for sure that Safepal hardware wallet has closed source this, so you can't verify anything coming from their QR code, and all other stuff they have is closed source.
I am not sure how this works for Passport hardware wallet, but they have almost everything open source like design and firmware, but you need to verify with them how QR codes work.
For DIY signing device SeedSigner QR code is simply a string of numbers representing each word on the BIP39 wordlist, and Krux signing device supports it:
https://github.com/SeedSigner/seedsigner/blob/main/tools/seed_phrase_to_qr.py