Recommendations for Meowscarada EX deck?

I'd suggest removing the Arceus line, it doesn't look like it synergizes well with Meowscarada. (Arceus works well in aggressive decks with lots of Pokemon V and big energy requirements, whereas Meowscarada works better in slower decks that want to play long matches.) I'd also take out one copy of Boss's Orders (2 Orders + 2 Escape Rope + Boquet Magic should be enough imo). Finally, I would reconsider the card-draw Supporter lineup in general; my gut feeling is that exceeding about 8 or so card-draw Supporters starts to make hands cloggy.

As for what you could add to replace those cards, I'd strongly suggest 1 Skwovet to synergize with the Bibarel. Aside from that, I'd look into single-Prize Basic Pokemon like Klefki, Miltank, and Mimikyu that can sit in the Active Zone and can (even without attacking) extend the length of the game. My reasoning is that if Meowscarada stays on the bench and the match lasts many turns, you will get to use Boquet Magic many times and your opponent will not have as many opportunities to claim Prize Cards. On top of that, stalling the game gives you more time to evolve your Pokemon and more time to draw into the cards you need.

Some other interesting ideas I've seen are Hisuian Lilligant VStar for its outstanding searching Ability, or a package of Rapid Strike Medicham V + Forest Seal Stone. The trade-off with those is that using more 2-Prize Pokemon typically leads to shorter games, but if you'd like to lean into that kind of playstyle then it might very well pay off.

Ordinarily for a control strategy I would suggest Crushing Hammer, but with all the Chien Pao running around I think that'd be a bad meta call.