Arc blade appearance are very bugged right now, they are completely white and you can't change their appearance.
Only archeotech rarity seem to be affected by the issue while i can't 100% confirm this, i have test blue and green rarity arc blade and they were normal.
If that help i have report other weapons with this issue and you have fix them back then.
If needed you can borrow my account choose Jezabel and equip the arc blade in my inventory you will see the problem immediately.(my psn id is in the short title)