They could have. But the likeliness is very low. The Ilkhanate, Golden Horde and Chagatai Khanate had some numbers of Muslims.Could the Northern Yuan convert to Islam
What would be the impact of this
When does this occur?Could the Northern Yuan convert to Islam
What would be the impact of this
I think it would have been irrelevant.Northern Yuan was barely an entity during this period of time,too fragmented and chaotic to be a coherent force,with the Oirats more or less marginalizing the Borjigins and declaring themselves Khans at one stage.According to wiki about Timur planed invasion of china one of Northern Yuan Khan, Engke Khan, grandson convert to Islam while he stay at Timur's court. I think best chance to have Northern Yuan convert is either they became very depended or even vassalize by one of Turkestan khanate at least for several generation to make it last.
But it is easier with Yuan Dynasty convert to Islam in the first place. Since although eventually they convert to buddhist, some Mongol even prince still convert to Islam.