#2 Kazuchika Okada

The past year has been the year of Okada. AJ Styles' WWE debut and first year was incredible in its own right, but even that cannot compare to Okada. Ranking at #1 in the PWI puts him at the top of the list as the best all around wrestler in the world.
By putting on stellar match after stellar match, Okada will go down as the best worker in Japan right now, and most likely all of professional wrestling. While only 29 years of age, Okada seemingly has not even reached his prime years. Some may argue that now is his prime and that it may last for a very long time.
New Japan has invested a huge amount into Okada and would do their best to keep him at all costs. The language barrier may also prove to be troublesome if he ever signed with WWE.
Not to take away from the talent of the WWE locker room, but the wrestlers in NJPW are capable of putting on much higher quality matches for several reasons. With all his star power, the WWE would most waste Okada's talent through poor booking and the lack of credible opponents.
Becky Lynch has been challenged HERE.