By just a little bit of research, I have found out that Musing **will** be creating an SMT for their website. Musing doesn't want to be completely be dependent on delegations and they want more freedom to reward user, that's why are looking forward to SMTs. -- Source Discord Server
Yes, Musing's owner and developer @jonching has already said that he will indeed create an SMT for Musing when it's ready. I don't think he has posted publicly about it, but it's been discussed in the Musing Discord server.