Question

When customizing keymap shortcuts, it appears the desired shortcut is assigned to other actions. It shows conflict dialog when trying to assign a shortcut:

Answer

Right in the dialog of assigning a shotcut, the list of conflicting actions is listed (before pressing "OK")

Also, one can search for the actions that are assigned to exact shortcut using the "Find Actions by shortcut" feature. There is a button next to the search text box. Click it, then press a shortcut on the keyboard. It will filter out actions that don't match the pressed shortcut, leaving the list of actions that share the shortcut: