Most suitable for MagSorc:
Altmer (high elf)
Breton
Dunmer (dark elf)

StamSorc:
Orc
Redguard
Khajiit
Bosmer (wood elf)
Imperial

StamDK:
Orc
Nord
Imperial
Redguard

MagDK:
Dunmer
Altmer

Preferably, it is the class that should determine the race (if we put aside the attachment to lore). Orc might be better for class A, while you could personally enjoy class B more. The question you should ask first is whether you want DK or Sorc.
Both classes are good as Orcs, choose the class now. From what I've seen Orc is very popular for StamSorcs

Orc is best everything. No believe nay says. You pick orc you auto win. Unless enemy also orc. Then it up to who can punch the hardest

Every race fits every class. Play the race you want to. Theres a 1-5% difference in the end but it really doesn't matter at all. Go for Orc if you want to you won't be worse than others.

Orc's advantage is the movement speed boost, which is very useful in PvP if you are trying to get to your target or run from your pursuer. Orcs also get boost in Stam and Health. The Stam part makes the race suitable for Stam builds, but unless you're going for optimal DPS build you can play whatever race you want, especially considering stamina is useful in PvP even if you're a magicka build. In fact you'll often find magicka builds that incorporate boost in stamina.

I wound like to try both stam dk and sorc
But I dont want the races to be duplicated
So I choose orc sorc and reguard dk, both dps

Is it good?? Or I should try imperial dk?