Yeah but the Ebony Warrior is Redguard so he would never have seen Sovngarde anyway.

true. But that means if the player was an altmer or khajiit, visiting soverngarde doesnt seem right. Even tsun says 'when the time is right, join us'. WTF?
Not true.
Belief shaped reality here. If the Ebony Warrior is faithful to this particular belief set and dies an honourable death there is no reason he couldnt go to Sovngarde.
Secondly, the Dovakhiin enters through a portal. There is absolutely nothing 'weird' about a Dragonborn to visit Sovngarde in pursuit of his destiny. Who is Dragonborn is chosen by Akatosh and has absolutely nothing to do with race.
The Dovakhiin through defeating Alduin is honoured by Tsun by getting a return ticket, that is, he can choose to go to Sovngarde when the time comes.
Once more, absolutely no weirdness here.