Speaker placement.

Not sure I understand, but I always prefer putting speakers on the short wall and giving them some space to breathe away from the back wall but still need some space from side walls as well. In that room I’d start with the speakers at least 3’ out from the back wall and 2’ away from the side walls and start there and then adjust to your liking.  You’ll also want to experiment with toe in — I tend to prefer the speakers firing just outside my shoulders, but all this is very speaker, room, and taste dependent so use these only as general guidelines to start and work from there accordingly.  Just my $0.02 FWIW.

If u wanna do nearfield listening feel free to put them on the long wall and do the equilateral triangle thing if that’s what floats your boat.  But that’s very different from positioning the speakers on the short wall, letting them breathe, and let the room reflections enhance the spaciousness of the performance.  Two totally different and valid approaches.  Just depends on your personal tastes.  Personally, I much prefer the latter, but that’s me.  The good news is, all this placement stuff is free!  So experiment to your heart’s content.  Best of luck.