Portable vs Window AC Units...

I’m in the same boat as you and contemplating the same issue. Richardo has stated the pros and cons of each. Portability, weight of unit and ease of set up is a big consideration for me.

In regards to portable units, from what I’ve read on a professional HVAC forum Whynter portable ACs or heat pumps are stated to be better units, and if you go this route you’ll want a dual hose unit. They are a tad more pricey than window units.
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Personally, at the moment I’m leaning towards a 12 to 14 K BTU Whynter portable dual hose unit to cool a larger area similar in size to your large bedroom, and smaller 5K BTU window unit, which I already own, to cool a bedroom.

The best portable units are the dual hose inverter A/C's. The midea dua smart inverter. They cost more but a traditional 14k btu portable a/c might have a 8k-10k rating under the new guidelines where a dual hose inverter unit will have a 12k rating. Toshiba has smart inverter units too (probably made by midea)

For the best bang for your buck, 5k btu window units will cool a bedroom, are cheap and small enough to be easy to put in the window by one person. I have 2 5k units and a portable 14k now. We actually use the portable in the hottest room in our house, I can hang meat in there if I shut the door.

I have a couple of the portable ones to assist my undersized split system and in my tool room in my shop. Def the way they don’t need the drain line anymore is a plus. Depending on the size of what you are wanting to cool, they would be the better option for what you are looking to do. Widow units are a pia by yourself. Don’t buy the cheapest just because it’s temporary though. I got a black and decker one at Home Depot and although it was 3-400 bucks and it wouldn’t cool my bathroom. The bigger LG works great

window unit:
harder to deal with, more efficient, cheaper

portable unit:
make sure it is dual hose