Earlier quoted context omitted.
I've used KeePassXC, and I think it's the best KeePass variant. I don't like stock KeePass because it's horribly slow under Mono (Linux/OS X). And I like but am not as satisfied with KeePassX because it lacks some features I like. From what I recall, the maintainers of KeePassXC got frustrated with the feature set and development pace of KeePassX, so they made their own fork. And they added nice things like TOTP code…
With KeePassXC you would do this by adding new entries for each alias and then reference the username and password values of the "base" entry. I believe the feature still isn't in a release, and the UX isn't there at the moment. The problem is that they can't deviate from the official KeePass database format, so adding something like aliases requires hacks like the above.
KeePassXC doesn't support KDBX yet, but they'r working on it[2].