They’re available as bundles in the store when a new set comes out. Usually each set contains 4 or 5 of them in a pack that you can buy. They also give the out as random cosmetic drops for certain win rewards.

These are the current LTR emotes:

Also, if you go to Profile -> Emotes at the bottom right, you can see if you have any already. I think they gave some out for free a while ago so you may have some in there.