There's really no way around it; you're just going have to experiment with placement. I wouldn't assume that you are going to get bad sound. Sometimes with an odd room, you can get lucky and have no problems.
If you run into some problems, here's something you can try that's not too expensive. Most room tuning treatments are made out of fibreglass. You can make some very good ones yourself. All you need are pre-made fibreglass panels (not the big rolls, but the kind that look like pictures that can be hung on the wall.) Wrap them in a fabric that matches the colors in your room, and that's it. Just put them where you need them. For your room, you may want to mount them on some type of stands and simulate a wall on the left side of the left speaker. Hopefully, that will give the speakers some balance and help with imaging.
If you run into some problems, here's something you can try that's not too expensive. Most room tuning treatments are made out of fibreglass. You can make some very good ones yourself. All you need are pre-made fibreglass panels (not the big rolls, but the kind that look like pictures that can be hung on the wall.) Wrap them in a fabric that matches the colors in your room, and that's it. Just put them where you need them. For your room, you may want to mount them on some type of stands and simulate a wall on the left side of the left speaker. Hopefully, that will give the speakers some balance and help with imaging.