@Skyknight #49445
I’m sure they exist but a person would have to be pretty far out fringe in their beliefs to make it work. Basic Buddhism supports reincarnation, Islam is like Christianity in being a one shot and done religion. You would have to be nearly atheistic to wed those two and at that point your probably giving up both. Also, Islam is very insistent about not letting in outside beliefs/rituals. Mixing Islam with another religion would be a big violation of basic principle.
On the practical side where the two overlap the population tends to be divided along religion-racial groupings with oppression and violence being standard. Publicly trying to mix the two might get you beaten/killed from either side.