@edent@mastodon.social -- I've just tested and that account also works fine with Hubzilla. I will mention that your implementation in this case uses url-encoded usernames while ours uses punycode. They should be able to interact just fine, but the fact that there are multiple ways to arrive at a solution could cause a bit of confusion for implementers.
You'll need to use punycode if you wish to federate with the diaspora protocol or email or any other projects or protocols which restrict the character set for usernames. So it might end up being a more flexible solution in the long run and should work fine with every other fediverse project today. ASCII-restricted software will just use the xn-- name; and all their links and buttons should work fine.
Url-encoding should also work, but perhaps not so universally and easily as punycode; as witnessed by the number of issues documented in this thread.