So where are you ranking Momoshiki and Kinshiki on your list, Q?
Just to give a rundown of their abilities, each are extremely specialized but very powerful. Kinshiki has three techniques; Byakugan, Malleable Energy Weapons, and a powerful strength-enhancing Jutsu. His strength was such that his blows were destroying the entire Chuunin Exam Arena, and split a smaller Shinju later on. His overall prowess was great enough to put Sasuke on the backpedal both times they fought, but he lost to Gaara and 2 other Kages in the end (with slight assist from Sasuke).
Momoshiki is also very strong/fast (but to a lesser degree than Kinshiki) and an even greater Taijutsu user. (Though he was overmatched against Sasuke/Darui/etc.) He has the power to absorb any ninjutsu with his left hand. Then, he summons a chakra pill that amplifies the power of the absorbed techs exponentially, and fires it from his right hand. He can fire multiple Justus at once, and has even absorbed techs like Biju Bomb and Shadow Possession.
After fusing they become much more powerful. They have all the above abilities on a higher level, standard blue Rinnegan powers like Chakra Receivers, in addition to some strange ability to alter the environment to fight for them. They were able to go toe to toe with Naruto/Sasuke as a duo, but lost in large part because they understood his power.
