For the first question, yes you can create multiple account derivations that are associated with one seed on either of those devices, and import them to a wallet such as Sparrow.
On the second question, I know a recent Passport firmware update enabled child seed functionality and nostr key generation. Not sure exactly how Coldcard compares in that regard, but after a quick search of BIP-85 it seems it’s supported:
Thank you for the information. It seems Foundation is a little better as it has a key manager that you can name the different keys you generated.
Seems that Coldcard you would need to write down what index number you used and for what.
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Your welcome. Your post looked lonely, and possibly the first opportunity I’ve had for first reply on SN. ;)
Safe to say Foundation devices focus on UI/UX through aspects like one you just mentioned is a distinguishing factor when comparing the these two hardware.
In the end, it’s best for everyone to do their own research, and assess what is more suitable to them. But there are many here who like to help, so I’m sure you’ll receive more information.
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Coldcard has something similar coming soon, I think they named it seed vault. As I understood, it allows you to store and label multiple ephemeral and BIP-85 seeds.
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