I wore mostly dress slacks and blazers with a nice top underneath for w*rk. If I knew ahead of time that I would be installing laboratory or computer equipment or making optical connectors, I wore black stretch jeans and wore a Tshirt. I could always throw on a knee length lab coat if I had unexpected visitors on a tour.
I did own 2 "power suits" for briefings and out of town conferences.
After I FIREd, I think I did the full closet cleanout during the 2nd year. I gave everything to my housecleaner, who picked out what she wanted and took the rest to her graduating class of brand new LPNs. I kept 2 blazers and 3 dress slacks for myself.
Now that I no longer have to prove myself in the w*rkplace, I bought and frequently wear girly sundresses and miniskirts in nice weather, something I would never have worn as a female Engineer. I even wear makeup these days.