Can I flash my S8(GM-950u1) to S8(GM-950FD) (INS version) to obtain VOLTE?

[Android Central Question]

I have an unlocked S8(GM-950u1) and I don't have VOLTE option. So if I want to have volte as an option, can I flash my phone to (GM-950FD)? If no, which firmware should I flash such that I get VOLTE as an option?

 

[Luffy_D]

If you get any way for it please lemme know...tho I don't have unlocked version but I have G955U (TMB carrrier). But I m using phone in India. Tho volte is shown on bit isn't working.