Unsheaths weapons every 2 seconds or after the following events:
'ADDON_LOADED',
'PLAYER_REGEN_ENABLED',
'LOOT_CLOSED',
'PLAYER_ENTERING_WORLD',
Weapons will only be unsheathed if the player is not [moving rapidly, in combat, swimming, submerged, or resting (in city)]
Only tested on Classic. There is no configuration, it does exactly what I needed and no more. If you want to change the behaviour, edit the code. I might add config later if I want it and feel like it.