Re: Kisame (samehada) and Bee vs Sannin
It really depends how serious Bee gets when things first start.
Jiraiya solos Kisame. Toad Oil Flame Bullet would be enough to counter most of his water techs. SM he reflexes are sharp enough to dodge other attacks. Then there's Goemon.
No Frog Song necessary here.
Here's the problem with B. He's rather fond of that Lariat. And yes it would mess Tsunade up if it made contact, but what would her strength do to him? She can he from the damage she takes and she has more durablability feats than Sasuke (Able to fight with cut abdomen, respiratory, and bicep muscles. Able to blitz Kabuto and Oro in that state actually. She also survived being impaled by two different swords, survived a Shinra Tensei FP from upclose and personal with no medical ninjutsu,etc.) So I doubt she would be as bad off as Sasuke was after Bee's Lariat. Also if she opts to do Pathway Derangement to Counter instead Bee becomes helpless and anyone can finish him off.
However if he transforms things get so much worse for the sannin. Without TBB I suppose the summons can help fight. But when TBB comes if they can't get out the way they are screwed. Though TBB isn't instant. So depending on how Bee handles himself determines whether he wins or loses.