Can't move mons from Home to Champions without washing through Z-A?

Hey,

I'm struggling to find an answer for this. I have years worth of mons in Pokemon Home. When I try to bring them to Champions, nearly all all have the no entry/red circle sign. When I try, I get the error, "This pokemon cannot be sent to pokemon champions"

There's only a few without that sign.

However, if I bring a mon into Z-A, and back - it becomes eligible for Champions.

Has anyone else hit this? Is this a case of the mon data being too old for Champions, and Z-A updates it for Champions?

I've already considered the Champions dex in this problem.