If you are on PC, (at least on my account) it only shows collectible emotes when you go into emotes screen via the collections menu (U).
If you want to get access to all the emotes available, then you have to move your mouse cursor over one of the collectible emotes in the emote window and select (F) - shows at the bottom - to assign, this will then bring up a different screen showing menus for all the emotes in the game alongside the emotes quickslots wheel.
Or if you know the name of the emote, you can just type /and the name of the emote in the chat window: