Garp(Family trio with Luffy and Dragon)
Dragon
Sabo(being a trio with Luffy and Ace )
Sanji(being Zoro rival and Luffy second wing/left hand )
Yamato(her father has it and she has a strong spirit)
Law(being a trio with Luffy and Kid )
Momo(his father and being Wano leader)
Kong(being fleet admiral who has Sengoku and Garp serves under him)
Mihawk(Shanks rival and Zoro's goal)
Weevil(self proclaimed son of WB and monstrous power)
Benn Beckman (most likely the current strongest YC, Katakuri has it so at least he should have it)
Xebec (has too many CoC users as subordinates)
King&Queen (maybe just because of their names.)
Great list. Mostly agree but I would omit some of the above (Sanji, Law, Queen and perhaps Weevil).
Add:
Enel (wanted to be God)
Wiper (Shandoras Oden, for me his potential if he had ventured to the Blue Seas is as high as Odens)
Aisa (seems like Shandoras Shirahoshi or Momonosuke)
Mont Blanc Noland (conquered the seas)
Calgura (great warrior who could have been even greater, see Wiper and Oden)
Sai (following in Chinjaos footsteps)
Ulti (has shown signs of it several times)
Dellinger (was only 16 but already kicking Bellamys butt. Prodigy that could have it)
Tama (she's got a commanding personality and is still only 8)
Fisher Tiger (commanded and united the fishmen)
Otohime (commanded and united the fishmen)
Buggy (he actually has a knack of bringing people together, what if it's been conquerors all along?)
Crocodile (I don't think he has it but he seems like a rival of Doflamingo so he could have had it but it got deactivated due to him being crusched by WB)
Vivi (don't know why, perhaps she has an ability to unite people that Imu is scared of?)
Shirahoshi (perhaps only possesses voice of all things or it's conquerors that she is using to rally the sea kings)
Portgas d Rouge (used conquerors to carry Ace for 20 months)
Woop Slap (Village Mayor from Luffys childhood. Hidden super power that looked after Luffy from afar as a favor to Garp)