#7 Apollo Crews
Apollo Crews can probably be now filed under a big signing that went to waste. No, Crews wasn't the World Heavyweight Champion for another big company, but he was still a major player in Dragon Gate and throughout the independent scene, and his signing brought some buzz with him. Following a lackluster run as apart of Titus O'Neil's 'Titus Worldwide' faction, Crews finally returned to singles competition last October but has done nothing of note ever since.
There were rumors for a while that WWE was planning on giving him some kind of a push and he did win a couple of matches on RAW for a few weeks running, but he has been barely featured on TV in 2019. Crews was drafted to SmackDown during the Superstar Shakeup, and I don't think anyone remembers when was the last time we saw him on SmackDown.
Either WWE reevaluates their plans for Apollo Crews soon, or I think he needs to consider re-signing with them the next time his contract expires. I think Crews is the kind of performer who may do pretty well if he was nabbed up by All Elite Wrestling.