Only Apple Watch 3 and 5 (not sure of 4), Galaxy Watch Acitve 2 (not sure of Active 1) and the latest Galaxy Watch 3 are supported by Vodacom and or MTN.
Also from what I understood it only works for calls and not data (when not connected via bluetooth) so you won't be able to remotely connect to your phone to receive notifications via LTE.. which I feel is wasted usability..