However, WM has, for example, a dress which gives Elegant trait when equipped (so it's actually a temp trait, because it will disappear if you unequip it). Is it safe now to port it in Pytfall?
// I thought you mean temporary traits (Like Caught a Cold) not normal traits being awarded/removed while girls has item equipped

Yeah it should be 100% safe now, that's exactly what I've been trying to get to work perfectly.
What happened today was:
I equipped Hinata (loaded without traits) with your Maid Uniform item. Equipping worked fine, she got an Elegant trait (Aggressive trait wasn't removed cause she had none). However when I took the item off, effects were reversed, Elegant was removed and Aggressive added

(that would cause a complete chaos in the long run).
So I went to WM for a consultation but system there while working better, still had fundamental flaws like a girl who has Elegant trait already and equips TWO or more items that should 'temporary' remove Elegant trait, looses her trait. More flows when you have a number of items that take away or add the same trait equipped at the same time (there is a chance that you'll get stuck with the trait).
In the end I came up with a three layered approach that should fix all these issues:
- Girls being awarded a trait for hard work/training while same trait is already being enforced by an item.
- Girl having a trait, putting on an item that adds the same trait, than loosing the original trait but still keeping the trait until item is unequipped.
- Girl having a trait, then equipping two or more items that should 'temporarily' remove or add the trait, without loosing the original trait in the process (trait should come back when all items are unequipped if items removed it).
- Trait being active if girl originally had a trait, then put on an item that removed it and another item that added the same trait.
It all needs to be tested by it should now all sort itself out...