@gniibe Sorry for bothering but I couldnt find any answers to this online, is there any ETA for the v5 specification being released?

In T6050#159616, @gniibe wrote:

Thank you for your report.

V5 key (which is used by Ed448) is not implemented yet. See the function convert_from_openpgp_main in gnupg/agent/cvt-openpgp.c, where it parses the version of the key; Only version 3 and version 4 are implemented.

Please note that the implementation is buggy and not for use, because the OpenPGP v5 spec has been changed since then.