OK I see. As I say I haven't played pokemon in a while and only found out Kleavor even exists yesterday (!)
A good feature on Showdown would be a pre emptive list of formats any given mon is allowed in.
Showdown is amazing, but a bit confusing at times.   I find I have ideas for teams only to end up cutting half of it out and spending 15 minutes  clicking on each format and praying that they're allowed, eventually finding myself playing a totally different format and team than I had originally intended. while I'm not bothered about winning or losing, I do want to see how (x idea - let's say, a copy of an in game gym leader or rivals team - or say, a team of all the legends or starters from a certain gen - that kind of thing) would play out in practice,  and more often than not its banned in some way and I end up doing something completely different, (that I'm usually not as enthusiastic about.)
I also find a discrepancy between when I validate on teambuilder then when I search for a battle. It just said my team was valid for gen 9 Nat dex any thing goes, then I went to battle and there was several things not allowed in it. Quite confused!! The list of formats/tiers on teambuulder also look different to the ones when you search for a battle.