Is there such thing as OTR steam oven?

I searched and couldn't find one.

Also, when studying the Gag combi Planning Notes, I noticed that one should allow at least 8" to the neighboring wall on each side.

I couldn't figure out if it had to be an empty space from the cabinet wall surrounding the oven to the room wall or the next cabinet or if it is OK to have another cabinet next to it, as long as the room wall is 8"+ away.

Gag owners, please help!