Sell which duplicate weapon

I have 2 Vectis. One of them has a catalyst. How do I tell which one, so I can sell the other one?

I can only identify them by equiping each and then going to the upgrade menu. I don't see a way to sell/mark/rename or otherwise distinguish them, so that when I go to the inventory screen I know which one to sell.

Well this is a crutch method, but - you can install a Forma in the one you want to leave for yourself. That will drop its level to 0 (and also show up in the right top corner of the icon), and you will clearly see which is which.

Other than that, I would advise writing a suggestion to developers to introduce displaying installed upgrades in the inventory, as it seems to be an obvious oversight.