Do either of their suits amplify their strength?
If so, how and by how much for each character's suit?
Asking about standard suits here.
I know each character has specialized suits that do all sorts of things to include strength amping.
Not concerned with those.
I can't recall reading either suit boosting their strength. Although it's possible with BPs vibranium suit, considering its vibranium attributes, may make it appear to alter his strength. I personally don't think it enhances his strength. But I can see how durability feats, with his suit in some cases, can be misinterpreted as strength feats.
__________________ Listen, boy. Have you ever had your scrotum pulled off by a mountain goat and seen him sell it on eBay a day later?
The only thing on Panthers suit that increases his damage output are the vibranium soles on his boots. They can be used to shatter or weaken objects with his kicks. But nothing else to my knowledge.