Is there a way to do this natively in a single set? Currently, if I have a layerwear outfit (with no outerwear) where I want the accessories to be a specific color, I need to have the outerwear matching that color in a separate set, switch to that, and then switch to the set without any outerwear on it, and it'll keep the last-used outerwear color.

I did this dance in the salon and saved the ensemble (beach wars outfit with no outerwear, but an accessory colored white by last-worn-outerwear being white), but upon leaving the salon and using the ensemble the accessory was black (the outerwear color of my other, usual clothes) because I guess the outerwear color doesn't actually save if there isn't outerwear.

Is there some simpler way I'm missing to do this one-click? Or is this just one of those "pso2 is an old game, it's clunky sometimes" things?

"PSO2 is an old game, it's clunky sometimes."

The only thing you can do is have an Outfit or Outerwear in your inventory in the color you want and just equip it, let it load, then unequip it after switching to the ensemble you are trying to do this for.

Dang, kind of annoying but oh well.

Interestingly while looking through layerwear I stumbled upon an interesting item that just got introduced this year in JP: A black choker that counts as outerwear instead of an accessory, specifically to help with this issue for outfits that you don't want outerwear with (it has a small circle on it that corresponds to the outfit color though) https://pso2.swiki.jp/index.php?C・C・チョーカーF

Would be neat to see us eventually get it, too. Still an extra item to lug around, but it's pretty non-intrusive.