Same for me. Just made a build where I reallocated certain boosts and replicated a build where those boosts did not exist (+7 on both shot powers & accuracies vs no boosts on either but same overall) and the one with boosts were slower/weaker shots. Same goes for strength. Testing removing all my boosts and seeing if the way my player performs is the same
Edit: I can already tell after 1 period that everything is exactly the same with and without the boosts. Shot powers & accuracies are the same as well as agility. Strength is the same (noticable through the shot powers) the only things I think are unaffected by the non-working boosts are acceleration, speed, balance, the awarenesses, and passing. Can't say for any other attributes because I have them maxed or I don't use them
Edit #2: after finishing that game I went back to polish my attribute setup since things were uneven due to the removal of the boosts and it seems that only sometimes the boosts don't work. I remade everything the same except passing, puck control, hand eye and offensive awareness and kept the shot power and strength the same as it was prior to removing the boosts and this time my shot powers were weak and slow. Weird
Edit #3: After taking a break, I tested my shot in the creation zone and now my build that did have the good shot is no longer good. And I didn't even touch that build at all. I think it's an EA server issue not doing whatever it is that it does (when it's even working that is...)
Edit #4: now no matter what my setup is the shot powers and accuracies are terrible. The only thing that's keeping my shots stronger than base is strength. WTF
Edit #5: I THINK I FIGURED IT OUT! When I was in the setting to find my origin account email, I went through the hospitality settings and set it to hardcore simulation. I just remembered now and set it back to regular simulation and my shot powers are back to normal. It seems that hardcore simulation basically negates the effects of the boosts slots
Edit #6: I have come to the conclusion that boosts used on either of the shot powers or shot accuracies do not work. It is better to just use those empty boost slots and put anythung else in its place. This also explains why when using boosts on slap shot accuracy when making a legend 3 Two Way Defenseman, the accuacy is terrible