Easy way to swap Relics/Implants?
This is a long-standing complaint and sadly there is no way to swap both relics/implants without opening your character sheet.
To avoid dragging you can right-click one or both of your equipped relics to remove it/them, and then you can right-click both of the relics you want to equip. That means the de-equipped relic(s) will be in the first open slot(s) your inventory had rather than where the other relics were, however, which can also be annoying.