Temporary Covers/Levelling

I’m trying to get OBW to 3/5/5. She’s currently at 3/5/3, but I just got a purple cover for her. Should I apply the purple cover for now so I can continue levelling her up then replace it when I get the last black cover I need for her, or sell the cover and just wait for the two black covers I still need?

Level her up now, U can always respec when u get more covers

I would keep her purple at 3, because I’d prefer to activate her skill earlier (assuming that you are using her already despite not being level max)
Selling the purple cover would also get you a little ISO.