3) Vodacom issue : eSIM in a phone and eSIM in an AppleWatch: technically yes it it supposed to work without any problem as these 2 independent eSIM are just linked to the same phone number under the OneNumber feature.
BUT : Vodacom One Number feature has a limitation (it's a flaw or a bug or whatever you call it). it only allows one eSIM per phone number under the One Number feature and physical SIM cards.
So if you had an eSIM in your AppleWatch and now you order an eSIM for your phone, the eSIM in your AppleWatch will be automatically deactivated .. there's no way you can redownload an eSIM for your AppleWatch if you have done an eSIM swap for your phone.
So at the moment, until Vodacom solves this issue, you have to choose whether you want your eSIM in the phone or in the wearable. if you want to continue to use your eSIM in an Apple Watch DO NOT REQUEST A SWAP TO ESIM FOR YOUR PHONE and keep your physical SIM.