Just realised this, when I was editing my sets. Only the defence and crystals are displayed.

So there are a lot of weapons where there correct damage isn't shown because they have multiple attacks. For example, scaling weapons don't show the stats for every tier, only their first tier. It's not a glitch, there's likely just not enough room to show every attack a weapon is capable of on the hover. SubetaLodge has done a great job of listing most of the attacks though (MW), but it's user-run so not all information is up for every weapon.

I knew that scaling weapons only show the first tier, but at least they show something. Guess I was just confused to see nothing at all. It's always a bit inconvinient having to check subetalodge for information that should be displayed here, though I greatly appreciate their effort of course. So if it's not a bug this topic can be closed.

You can ask or (the Battle admins) why it is that way if you want a better explanation.