1. Frostflame weapon http://www.db.pandawow.me?spell=131554/frostflame-weapon#used-by-item-set
2. As of right now, while wearing the necessary set of 4 items and imbuing your weapon with flametongue, shaman's abilities do not apply Frostflame weapon debuff. Can't really show it in combat log because it does not deal damage, rather apply a slow debuff on enemies.And i can't prove that i am not slowing someone with screenshots because of many reasons. But you can see it ingame for yourselves. I can help you demonstrate the bug with my character "Kaaravs", just whisper me ingame.
3. How it should work as it states in wowhead- http://www.wowhead.com/item-set=-1097/prideful-gladiators-earthshaker . If wearing 4 pieces: While your weapon is imbued with Flametongue Weapon, your attacks also slow the target's movement speed by 50% for 3 sec.
4. 07.08.2017.
5. Realm x100 was the only realm i tried this on
6. I would give this bug a priority of 8, because if this is not working, the enhancement shaman spec can be kited too well in pvp and has no other slows apart from frost shock and a totem.