The most realistic of the mentioned options seems to be Kabayel, who owns the EBU belt, because the other three are practically guaranteed championship fights - Zhang for the WBO title, and Wallin and Hrgovic for the IBF title.
The working date for Joshua's fight is December 23, although Eddie Hearn's choice for that day could also be Chris Eubank Jr. vs. Connor Benn, but both fights are likely to be rescheduled if Tyson Fury and Oleksandr Usyk decide to fight on the penultimate weekend 2023