Is it permissible to engage in Mutah under the conditions of Misyar marriage, given that the one being married is a Sunni Muslim?
There is nothing in our authentic books called Misyar marriage. This name was been used recently by some of our Sunni brothers for certain type of marriage which does not need staying together.
Mut'ah marriage with all its conditions are allowed, no matter what people call it.
Wassalam.