I mean, you can just narratively guess who will win here:
- Like Law, Kid has had his arc focus as a protagonist/ally. We barely know anything about Shanks or Blackbeard.
- As mentioned above, hes already protrayed as an ally Luffy, regardless of his competitive vibes. Killer has already lost to Zoro.
- Neither Law or Kid are Yonko, and thus are not backed by fleets or remotely have the same level of presence with commanders. BB/Shanks have 9-10 commanders, the same as Luffy.
Its just clear as day. Kid winning does absolutely nothing for the story. Law winning does absolutely nothing for the story. BB/Shanks winning give them the RPs they need to directly compete with Luffy, along with their fleets and commanders.
Not even saying this as a Shanks fan. Its just painfully obvious that BB and Shanks are Luffy's direct competitors, not Kid/Law, on every single parallel.
They will be allies in the endgame, but not competitors for One Piece. That makes no sense as their crews just do not measure up, even if Law's was looking pretty cool a few chapters ago.