#4 WWE Universal Champion Roman Reigns
Even if Ospreay decides to join WWE, he will possibly never be treated as a constant main eventer with multiple world championship reigns. However, like Cesaro and others, he may receive a shot or two at the title.
Roman Reigns has never underdelivered in his title matches since the start of his lengthy WWE Universal Championship reign. A hypothetical match between Ospreay and The Head of the Table would be magical, with Reigns' power and cleverness tested by Ospreay's superhuman reflex and endless move-set.
#3 Former WWE Champion Seth Rollins
At one point, Seth Rollins tried too hard to claim a spot as the company's social media protector. Aggressively defending his promotion over Twitter, Rollins would go on to partake in an ugly social media river with Will Ospreay, with The Messiah asking for a comparison of their bank balance.
Rollins later apologized to Ospreay over his tweet but maintained his opinion of WWE's greatness. The former WWE Champion has since lowered the intensity of his social media game.
A match between the duo would thus have an automatic history, with the in-ring skills and charisma of both competitors possibly creating an instant classic.