Single Room with AC Heat Issues

[bombermwc]

So i have a normal HVAC guy, but im curious if anyone has had an issue like this and what they may have done.

We have a room that has 3 outside walls. It also has a high arched ceiling. It's the last room on a hall and tends to collect hot air and not cool down. The thermostat happens to be right outside of this room. Mostly its an issue in the summer because when its cooler in the winter, it's much easier to heat it up. It's used as an office so that's why its not much of an issue in the winter. In the summer though, it keeps the house hotter than it should be.

We had a sweating window but we had that repaired and also have UV curtains on the window as well as blinds. When we use the ceiling fan, it just seems to circulate the hot air and not bring in any cool air in.

So i'm wondering if anyone else has had this sort of issue. The room seems too small for a minisplit and so im wondering if there is some sort of even smaller AC option out there. The portables a/c units require the the air exhaust somewhere, but i dont have anywhere to shove the hot air. Possible cut to send it to the attic???? I'd like to be able to set some sort of timer for it to time it with the rest of the house too.

I've attached a couple of pictures (dont laugh at my quick 5 minute MS Paint drawings) to help show the layout.