Yea I can use hotspot on my multiSIM account.

Nope, it is firmware based
For example, if u insert digi sim, it will support digi volte and vowifi
If u insert celcom sim, it will support volte only and dun have vowifi
If u insert maxis sim, u wont get any

This same goes to iphone /huawei/larger phone manufacturer

Of coz, all the sim above shud provision volte in their respective network first.

Else, ur maxis number is not volte, insert to iphone 11, then u won't get any volte.

Profile + phone firmware = volte
Also for 5g, if u remember samsung dun wan enable for umobile 5g even though umobile willing to provision all user to 5g.
Profile + not support 5g note 20 ultra plus plus plus 5g = cant attach to 5g