Well then it is going to be quite compromised from the get-go. One speaker will be close to one wall while the other will end up nearly in the middle of the room. The two speakers will be producing completely different sound fields and frequency responses.
Generally you need to decide if a long wall setup or a short wall setup would be more practical for a given room then centre the screen along one of those walls and then naturally the speakers will also end up with similar distance to their corresponding side wall.
For example, just recently I was measuring the individual frequency response from my two front speakers and noticed that one had a large null around 60 to 100hz while the other one didn't. It was because I had a 100mm offset from dead centre of the wall my screen was on. The right speaker was 1200mm for the right hand wall while the left speaker was 1400mm from the left-hand wall. Moved my TV and sofa 100mm to the left and repositioned the speakers accordingly. Now both speakers are 1300mm from their respective side walls. Soundstage imaging dramatically improved and also their measured frequency responses look a lot more similar.
If you really do want the best position for your speakers then there is no escaping the fact that you will have to configure a room around the speakers once they are in that "best position". Otherwise don't kid yourself and just put speakers wherever it suits and fits in with the existing configuration.