Epic Games-exclusive Stahlta Shock Rifle Skin provides minor buff to weapon.

[Kellurin]

Unskinned Stahlta alt-fire has cooldown (until weapon animation is in ready-to-fire position again).

Stahlta Shock Rifle Skin alt-fire has no cooldown, reactivatable immediately after firing. 

Showing lack of cooldown using skin: https://gyazo.com/d2261903dcf5e60f063910aa6787b25d

[Kellurin]

Noticed it was placed in incorrect subforum, sorry.