Mine is split in the sense of having the main keys in the middle of the keyboard on your strong fingers (like the old typematrix which was the first ortholinear keyboard I ever used) it’s not in separate modules like a kinesis or ergodox obviously. I don’t know if that would work on a laptop without it being excessively wide.
For my personal mix of tendon and joint problems actual separation isn’t helpful because some pronation is actually good for me. But obviously that’s going to vary.