A few questions that I think could play a factor in the outcome of this fight are:
Did Khabib reduce his pace in the 3rd-ish rounds of his last few fights because he had to, or because he could?
If Khabib does tire more than Tony, can Tony actually finish him?
If this fight goes into the later rounds, I wouldn't be surprised to see Tony more active, but it's hard to see him putting Khabib away. The guy's never been in trouble for even a minute in any of his UFC fights, and even if he drops the championship rounds to Tony I've got to think Khabib winning the first 3 is likely.
IF there's a finish, I see it being along the lines of round 1 of Lee vs Tony (which I realize wasn't a finish, but close...just rewatched it, great fight). Tony can sub just about anybody in the division not named Khabib.
Ferg has the best chance of beating Khabib in the division, but I don't think it will be enough. Unless Khabib gasses as hard as staph-Kevin Lee, which we have no reason to expect, I think he wins one way or another. Tony really does have near-GOAT cardio and an amazing ability to recover, but Khabib just doesn't get into trouble - on the feet, on the ground, or with his energy.
Also curious to see how Khabib uses his jab, and how Tony responds.
Pleeeease just fight already.