The 19-year-old has been attracting growing interest from Europe, and a potential move could mark a significant breakthrough moment as he looks to establish himself on the international stage.
Earlier this week, reports emerged that the French side have tabled an attractive offer to Pirates for the youngster's signature.
Speaking on the Soccerbeat podcast, Mokoena believes a move to Ligue 1 would provide the perfect platform for Mofokeng to kick-start his career abroad.
"I think for the young man, it's been two seasons of offers coming, and some have declined. If I were him, I would really jump at this opportunity because the French league is quite a good league to start his international career," said Mokoena.
"If I were Rele, I would be on that first plane to France as soon as the season ends," he added, before pointing out areas the Pirates and South Africa national football team youngster still needs to improve to succeed overseas.
"There's also one aspect that Rele needs to work on. You could also see in the friendly game against Panama national football team that his physical attributes need to get better. I think he needs a little bit of that, especially in that number 10 role.
"I think that is something Monaco is going to try and work on because they are very physical out there. You know the boys are big in France, and you have got a centre-back who is 1.8 or 1.9 metres. They are very tall.
"That's the little aspect that can be improved in his game, and he will fit in like a glove at Monaco. Plus, they are playing beautiful football. I've been watching some of their games, and they have a lot of young players in the team, which would be good for Rele," concluded Mokoena.