If you mean OpenPGP Card v3 standard, no it did not support cv25519 ed25519, but some other curves up until v3.4. So if there is a specific specification bringing this feature, can you might refer to the specific version? Otherwise, I think this task is still valid.
I remember the problem being the card manufacturers that are not interesting in cv25519 (yet).

Well, I surely would agree (and this is only a proposal anyway), but my point here is, that OpenPGP Card does not support Curve 25519, so that one *have to* choose between those other two. Considering me a tinfoil hat person, I would rather not choose NIST, as many others wouldn't too.

works just fine, thx!

Using a smartcard it should be possible to set a cache-ttl value so that not only on-disk keys but also the PIN used for unlocking the key on the smartcard is not cached longer than the given period in cache-ttl. Until now you have to plug out and in the card by yourself to get this working. Alternatively you theoretically could set a config in scdaemon to power off the card after some time ("card-timeout). It could be a solution to set this config automatically if cache-ttl option is used.