A black foreign diplomant appears in a major trade city comes and thinks his culture is better?

You mean this guy:

Mansa Musa, also known as Musa I of Mali, was the ninth Mansa (emperor) of the Mali Empire, ruling from around 1312 to 1337. Musa was born around 1280 and died around 1337.

he is best remembered for his extravagant pilgrimage to Mecca in 1324, which included a caravan of around 60,000 people and an immense amount of gold, significantly affecting the economy of Egypt due to his generous spending and gift-giving.

So what is he doing in 1403 Bohemia, 66 years after he died?

Or is he just a fictional character with the same name? If there's no historical basis for the character, then he doesn't have a place in a game aiming for historical accuracy.

It's understandable that right wing gamers aren't going to be happy about a game set in 1400s Bohemia suddenly introducing a black guy after everything that's happened in the last 10 years, but these guys just completely cognitively shut down partway through reading the tweet thread and it's not possible to communicate anything meaningful to raged out retards. It's not even "a black foreign diplomat", it's explicitly stated that the black guy is connected to the court of the Sultan of the Ottoman Empire and then the very next tweet explains that there's a reason for the way he's talking! He's not turning to the camera and saying "back in Wakanda, we call our sons Trayvon in honor of a great hero", he's not wearing the fat black woman from Concord's power armor, etc.