My main character (MC) is level 5. I decided to (finally) level it up a bit.
When I select the character and change the element, the game flashes and displays a different character instead.
Please see attached screen shots.
Steps to reproduce:
Filter character list to find MC.
Select MC.
Click Switch Element.
Click a different element icon.
Click Switch.
Result: System displays the highest-leveled NPC with that element on the switch elements background.