Eight tails is so *bleeping* underpowered that it isn’t even funny. Half of Kurama is stronger than all of the Eight tails (minus a horn and tentacle). It’s bloody ridiculous but it is what it is. Minato without even trying.
Minato kills low diff any version below BM , Hirashin + Rasengan is too much for Bee .
In BM, Minato got the tools to seal him, between high level Fuinjusu (Hakke Fuin), chakra barriers (he got one that even holds the Kyubi), Yatai Kuzushi (capable of holding Full Kurama for few seconds) , Hiraishin,.... He won't have much trouble dealing with him .
Minato also got the edge on intelligence and battle tactics . Not to mention Minato got better portrayal (we are talking about the one who was shaking just by hearing Minato's name) .
Killer Bee.Minato need to place tags which would not happen when Bee has sword 8 style which overpowered a weakened Sasuke who is faster than base minato.KCM has utterly poor feats with hiraishin let alone footspeed.EMS Sasuke saved naruto before he could.Bee closes gap and kills him with widespread BijuuDama.There is no way Minato wins I believe.
I remember some such spheel about Naruto's 4 trigrams seal being double-layered or something, and then one more layer was added by Orochimaru(although shoddily done), which made it impossible for Naruto to draw on the Kyuubi's chakra.
The Hachibi is sealed in with the Iron Ox seal, but I really see no reason as to why Minato can't just add a 4tri seal over it as another layer, or use the same sealing jutsu Orochimaru used, both options which would theoretically separate Bee's Chakra from the Hachibi's.
Therefore, I honestly think Minato can easily win this with his mastery of sealing jutsu. Aside from perhaps the god-tiers, I can't think of a better fuinjutsu user than him.