You can ship whatever the heck you want.
There are no “rules”. You might not gain certain followers, but it’s your blog so do whatever the hell you want with it.
I do. I post about Megstiel anytime I see it.
Hell I was just reading a Megstiel fic today. And I’m also in the middle of a longer Destiel fic.
And hell, I ship Sastiel too.
Ship them all three together. Ship all four. Who the fuck cares. (Obviously people who get too into shipping and think x ship intrudes on their ship but eh.)
Life is more fun that way.