Noob Questions

#1 I know how to change final cut scenes, but is there a way to set it to random? Like it does 1 of the 5 each time. (Especially during limit events where you can't change characters and have to do the same one each time)

#2 i play online and a rinne sasuke has the almighty push move but when I pick that same sasuke and try to change his moves it doesn't appear, how can I buy or get my character to have the moves?

#3 When I fight I'll hit a character, there's a break pause and a blue spark comes from the character being hit and I get knocked back. Is that an item or something. (Kinda like itachi's exploding clone but not really)

#4 Who of now do you think is the most OP character, just in your opinion?

#5 anyone on PS4, that's decent that doesn't spam like unbeatable moves like that kaguya ice move that want to help me out get better?