Yo, angelo I will help you with a bowser specific in this post(will edit this post only alright?)
Bowser- ok, this is an interesting matchup his edgeguarding can screw you over so much. One of the keys of this match up is to use hit and run tactics, or even more effectively jc grab alot to dthrow to knee, or you can kill them at low percentages with a u-throw combo by u-throwing to uair to a ff then uair again he will usually be a good distance and then lead off with a knee, you can recover still but, he will ie in this case most often. this is actually hard to do because their di completely effects the distance and how many times you have to u-air. Also, your nair is vital. On bowser it stuns him long enough for you to l-cancel to a grab. Your grabs are vital overall in this match-up. Bowser's arials ecept his dair match up or over ranks cf in priority. YOur Raptor boost is very useful in this matchup for tech chasing from the d-throw, to a uair combo. BOwser's recovery is actually pretty good. But, a dair can kill this because of how predictable it is. Another problem is the whirling fortress from shield. it can combo you up to about 80%.
NOT DONE YET!