Poaching shouldn’t affect the macros at all. I put chicken breasts in a freezer bag with salt, pepper, garlic, basil, and sliced up carrots, celery, onion, and lemon. Usually use the frozen cubes of garlic and basil. Just enough chicken stock to keep everything wet. Seal it up and poach it in a sous vide cooker (best $5 I ever spent at a garage sale). It comes out with a mild flavor. The chicken usually ends up chopped up on a salad, in spaghetti sauce, in a curry, under some salsa; any of which give it more flavor. But the poaching keeps the chicken breast moist with a great texture–which I’ve found makes a bigger difference than flavor.