Conor was hit with a $50,000 fine -- and will be eligible to fight again on April 6.

Khabib's suspension is a little different -- he was hit with a $500,000 fine and a 9-month suspension ... with the ability to get a 3-month reduction IF he makes an anti-bullying video.

Neither UFC star was present Tuesday when the case went in front of the Nevada State Athletic Commission. They each had lawyers appearing on their behalf.

The board agreed to a 9-month suspension for Khabib -- with the ability to reduce the suspension to 6 months if they're satisfied with Khabib's PSA video.

Khabib has about a month to complete his video if he wants to get the full 3-month reduction.

The suspension is retroactive to the Oct. 6 incident -- meaning if his PSA video is approved quickly, he'll be able to fight again in April.

Of course, Khabib went berserk after defeating Conor in the 4th round of his Oct. 6 fight at the T-Mobile Arena in Las Vegas -- jumping out of the cage and fighting a bunch of people in Conor's corner.

Khabib's cousin, Abubakar Nurmagomedov -- an MMA fighter who was also involved in the brawl -- received a 1-year suspension and a $25,000 fine.

It's also worth noting ... the committee issued a stern warning to fighters regarding pre-fight trash talk -- saying possible suspensions could be levied if the heated rhetoric continues.

Remember, Conor fired off several offensive barbs toward Khabib leading up to the UFC 229 fight ... saying Nurmagomedov was a "little rat," a "fanboy bitch" and a "backwards c*nt."

Conor also went after Khabib's manager ... accusing him of being a terrorist who was pulled off a plane on Sept. 11, 2001 and detained by authorities.