Tight 90 degree turn for outdoor EMT
If surface mount and going around a corner we usually use conduit bodies.
I usually use LB’s the opening is on the back and they have gaskets.
It is nuts since conduit is a wet location outside but rain tight couplings are required. These are usually compression type.
For drainage, I usually drill a small hole (1/4” or less)  in the bottom of my receptacle or switch boxes outside or any place I have splices I don’t want the fitting to fill up with water.
There are short radius 90’s but I don’t remember these approved for wet locations where most LB’s are.