As far as I know, as long as both engines (non-ABS vs ABS) have the same country code and are the same year model, the engine of the 1st gen Wee is the same. The major difference between the ABS vs the non ABS models is, a different wiring harness for the ABS related connectors, the APS pump, the ABS wheel sensors (front and rear), the extra ABS brake hose, the ABS related fuses, the storage capacity of the under seat tray and there is also less wattage available for accessories due to the ABS pump wattage requirement.
I would say that to make 100% sure, one could draw a parts list on both the non-ABS and the ABS, then do a part by part comparison of ABS vs non-ABS part numbers, for any differences.
Feel free to correct me, if the above is incorrect.