Just a split or an ortholinear split? If you're just looking for a split keyboard there's options like the Kinesis Freestyle 2, the Matias Ergo Pro, the Mistel Barocco and other random little brands. If you want Ortholinear, thumb clusters, etc. then you pretty much are left with the Moonlander, Ergodox Ez, the upcoming Kinesis Advantage360 and building your own.

Also if you don't care about fully split keyboards then you get options like the Kinesis Advantage 2, MS ergo boards etc.