Mendes had Conor on his back because he's the only wrestler Conor has ever faced. Who are you trying to kid?
Khabib would absolutely handle Mendes, and Conor on the same night. You're comparing a FW to a guy who manhandles Rockhold and is said to feel like a LHW/HW to those who have been underneath him.
He has way more of a diverse range of td's than Mendes and a single to close the distance which is superior against Conor's wide sprawling stance than a power double.
Khabib also has vastly superior top control. Conor won't be let up. He's nearly defenseless off his back. Khabib will eat him alive.
Conor has been fed midgets and strikers in his entire career.
The only times he wasn't were against Nate (non midget) and Mendes (wrestler) and the only reason he took those unfavorable matchups is because they had no training camps and were last minute fill ins. Both of them gave him fits. Wake up and smell the roses.
27-0
Khabib is the favorite for a reason. GSP picked Khabib against Conor, the same guy that picked Conor over Diaz 2 and Alvarez. Not because he's emotionally invested, but because, being the GOAT, he understands how easy it is to nullify a single weapon (left hand) if you can actually wrestle.