I doubt that McGregor beats Floyd as convincingly in a MMA fight, if and only if, Floyd is motivated to fight MMA.
Listen to McGregor's post-fight analysis, he recognized that Floyd used some techniques that could easily work in MMA. So, Floyd is not that far off from being a MMA fighter who can challenge McGregor in MMA.
Would Floyd beat a Kevin Lee in MMA? I would even consider betting on Floyd, because Kevin Lee will shoot, take him down, and apply the RNC. That is Kevin's fighting pattern.
This is not how McGregor fights. MMA fans using other fighters' fighting patterns to predict Mayweather vs McGregor in MMA is inaccurate.
Look at the way McGregor has fought thus far in the UFC, Floyd will have a better chance of beating McGregor in MMA than McGregor had of beating him in boxing.
Just my opinion, based on McGregor's fighting style. McGregor is not Randy Couture.