You could but expect tissue damage as the hammer coral has sweeper tentacles and the flower pot coral can extend its tentacles well past its base and also has stinging capabilities.
Both of those are considered “aggressive” and that’s because they send out tentacles up six inches in search of food. Good rule of thumb is to always give at least 3-6 inches of space between corals. ( always exceptions)
I definitely wouldn’t. I had a red goni years ago that took a sting from a frogspawn. Despite iodine dips the goni never opened again and died. They were about four inches away, maybe a little closer. The frogspawn threw out a sweeper. These euphyllias are common corals and I have always had them but I definitely learned to respect their space more.