What are your aquarium parameters, ammonia, nitrates...? How many and what types of fish are in what size of tank?
As for the Angel fish and the Gourami combo they were great when they first were introduced I’ve had the blue Gourami before anything else in the tank. When the angel fish arrived all they did was follow the Gourami around they didn’t harm it at all, they stopped doing that a while agoGourami are typically top dwelling fish. The dwarf, the 3 spot and its color morps, the pearl and the moonlight are normally at the top more then anywere else in the tank.
Do you mean that it is in normal fish position, like in the picture, but near the gravel? not laying sideways or with his nose up right? Just kind of hovering near the gravel?
Somtimes individual fish act in unexpected ways. how long have you had it? why did you remove his plant? Is it eating?
In the second picture it looks like your tank is only have full. Are you keeping a half full tank? The current might have scared/disturbed him into hiding. The angel fish may have scared it into hiding as well, gourami and angel fish are not really a good match, as they are both territorial top dwellers.
My Blue Powdered Gourami usual activity is staying at the bottom of the tank, it usually looks like he lays on the gravel but standing up. I don’t really know if that’s even normal behavior for a male blue powdered Gourami. But today I removed one of my plants and he’s been at the top of the tank.
Is he breathing heavily? If so, I've had this problem before with my betta, but I'm not sure whether would it work, but what I did was a 80% water change till my betta still had water, and then add aquarium salt.
Update Blue Gourami: he’s leaning to the side now, its 5 and the fish are usually sleep at this time or atleast roaming around the tank, the blue Gourami is leaning to its side now and I’m not sure if this is normal behavior of a blue powdered Gourami