#8 Henry Cejudo.
Last on this list as there was no Mighty Mouse trilogy to truly separate himself as champion, and when he beat TJ, it was against a guy who literally was injured and would retire after the fight. Cejudo did not fight in the division before getting a title shot. Cejudo also never defended his BW title either.
#7 Jon Jones
Cyril Gane was not proven, hw division was incredibly thin at the time. Jon Jones was able to skip the line based on his popularity, as he was not active in hw, or active in any division for that matter. Jones has his eyes on old man Stipe instead of Pavlovich, who everyone knows is and has been the toughest fight in that division. Years of steroid use and steroid bans during his LHW title reign also gray his legacy.
#6 Georges St Pierre
Had his entire career overlap arguably the greatest MW of all time in Anderson Silva. GSP waited for 3 champions to take over the mw division before he would finally dip his toes in that division. Granted Bisping was on his last leg, had one eye, I consider a 1 eye, one foot out the door to retirement Bisping, a more dangerous threat than Cyril Gane or TJ Dillashaw. GSP did not fight in this division before getting a title shot as he used his name recognition to jump the line. This was the one and only time GSP fought above his weight class.
#5 Conor McGregor
Never had to fight in Lw division to earn the title. Used his one mega fight with Aldo in a stacked division to convince UFC and fans he did not need to defend in that stacked division, or rematch Jose, instead he could skip the line to face Eddie Alvarez. Stylistically this was a bad match up for Eddie, however Eddie was closer to his prime and a more dangerous threat in his division than the 3 above two division champions’ opponents.
#4 Dan Henderson
One of the few two division champions who actually fought more than once in each division. He gets credit for becoming champion in two stacked divisions. Why he isn’t ranked higher is because he had lost the mw championship when he fought Wanderlei for the LHW Pride belt(MW). While Hendo was the first and only non HW to ko The Axe Murderer, Wanderlei’s invincibility at that point was not viewed as high because Wanderlei was coming off a head kick ko from Mirko. Even still, Pride Wanderlei was a monster and to ko him in the fashion Hendo did, truly epic. Hendo would go on to fight in multiple weight classes against the very best, such as Anderson at MW for the belt, Rampage at LHW for the belt, and even fought prime Daniel Cormier as at lhw as well. No skipping the line, all title shots=EARNED
#3 Randy Couture
Won the Lhw belt by earning it via fighting and winning. Won the HW belt by earning it via fighting and winning. Retired for one year after fighting 4 years in the LHW division, came back to fight dangerous Tim Sylvia at hw where Couture had an age disadvantage, size disadvantage, and weight disadvantage. Tim Sylvia was a much greater threat than other champions who would eventually lose to a 2 weight class champion, styles make fights and this fight was tailor made for Randy. Even still, he had to get it done against a mammoth of a man and did so in dominating fashion. The roof came off that night. Not bad for an old man.
#2 Daniel Cormier
Had prior experience in the HW division and was actually undefeated in that division before going down to capture the lhw title in which he earned the lhw title shot. Stipe is one of UFC’s most proven HW Champions and was the favorite to win going into that fight. Much tougher test than the previous two time champions. He would successfully defend the HW belt 1 time before losing it again to Stipe in the rematch and trilogy fight. Why I slightly put DC ahead of Couture, is b/c DC proved he can beat heavyweights as he had more fights at hw than lhw when he became lhw champion. His competence at HW was already proven.
#1 BJ Penn
In 2004 BJ Penn was considered the #1 lw in the world. Due to contract issues with UFC, he was not considered the “UFC LW Champion”, however universally he was for sure the best LW fighter in the world. At that time, Matt Hughes, was not just the UFC Welterweight Champion, but was the most proven Champion in mma not named Fedor. Hughes was demolishing the best at 170. BJ Penn came in with pounds to spare. While technically BJ Penn did not hold two belts at the same time, his challenges were the toughest. BJ did not start fighting above his weight class until that first Hughes fight.
Some may disagree with my rankings, but I was a fan of the sport for all of these two division champions and based on how the sport was at the time, these are my rankings of two division champions and I’m sticking to it…for now 
