Mosa is implied to be Shirahoshi. Mosa tells Loki there are problems where they are and they wont talk for a while.
I dont think its Blackbeard (he was just at Pirate Island like a few days prior), but its like everything else happening around the world. Chaos.
Yeah, but I don't really know why this Mosa-Shirahoshi nonsense kept being around. At least other clearly wrong theories like Gaban-man marked by flames were abandoned.
It can't be Shirahoshi, if not for simple logic (and there are various reasons for that), because of clear hints and proofs it's not her:
1) Shirahoshi talks differently:
2) Also, I know Oda is senile, but in the manga Shirahoshi
literally said that she could only talk to Megalo:
Not to mention it makes no sense and there is no logical connection for Loki to have ramdomly get a Deden mushy of Shiraoshi, Denden musho who doesn't even have Shirahoshi's features, etc.