My bet is on Neko.
My reason behind that is based on a theory I've had for a little while now.
If Jinbe appeared earlier than Neko, it will ruin Lady Toki's prophecy....
Just to refresh, Lady Toki prophesised of nine shadows / samurai that will take down Orochi. These "nine shadows" were hinted - at some point in early Wano - as the nine red scabbards, but that isn't the case now.
Why?
Because right now, there are seven scabbards sailing to Onigashima to attack. Two are missing: Neko and Denjiro; this means they're not fulfilling Lady Toki's prophecy; the raid on Onigashima will be a failure and some may have a death sentence as a result; the traitor could also be among them as well.
This means Lady Toki didn't refer to the nine red scabbards as the "nine shadows"... these nine shadows are actually the SH crew - which is why it took 20 years for Kaido to be defeated and Wano liberated:
Luffy
Zoro
Sanji
Franky
Robin
Brook
Chopper
Nami
Usopp
They comprise "nine members" in total, which ultimately means they are the "nine shadows" in Toki's prophecy (the supernovas in Wano; even if all the supernovas gang up against Kaido, they only number 7). This also explains why Lady Toki sent Kinemon 20 years into the future - it's because they are the key to get the SH crew to show up in Wano, fulfil that prophecy and take Kaido's head, liberating Wano.
If Jinbe appears, he will obviously be accepted as a Straw Hat, and this will break Lady Toki's prophecy. My bet is that he'll appear probably much later... most likely as a homie - this way, Oda would make him present in Wano, but not be able to participate with the SH crew in the fight against Kaido.. this way, Lady Toki's prophecy will not be broken.