Please Blizzard!! Don’t let the expansion come and go without letting us have Venthyr as an Allied Race and remove Underworld with Vampires versus Werewolves 
Oh I hope not, sorry. I am SO over allied races, and these are allied dead races. I say let them stay in the Shadowlands and if anyone needs new races to play, have them create interesting ones which we don’t have to grind our butts off to access. I pay for the game, expansions and my sub, and that should be enough to let me play any race on the creation screen when I log on.
we have an equivalent already, and they’re called nightborne.
Roll a Night Elf Blood DK with dark skin and presto! Instant Venthyr! 
They are reskinned nightborne.
i hope they don’t get added. I really wish allied races had been implemented more as sub races and were just additional cosmetic options; adding more flavor to the already existing races.
Allied races (in the form they’ve been implemented) has IMO just diluted the pool of NPC characters and added even more drama to people’s perceptions about racials and balance. I also personally am not a big fan of how almost every race on azeroth now is either horde or alliance. Makes the world a littler duller IMO. I find it more immersive when there’s lots of other nations/factions besides just the playable ones.
I know many players don’t care about the lore, or sometimes even dislike it if it’s creating restrictions, but personally I’d rather not see any of the shadowland races come back to azeroth with us since to me it’d seem very odd and out of place that these guardians and stewards over the realms of death decide to quit their jobs and join us for our silly mortal squabbles.
obviously this is mostly (if not entirely) subjective and purely my own thoughts and feelings but those are some my thoughts on why i dont wan’t Venthyr (or any other SL race) to be playable
Venthyr are one of two things: created by the Shadowlands (Denathrius specifically) or dead souls who decided to become them. Their job is to help run the machine. They aren’t coming back to the mortal realm to screw around with Horde and Alliance permanently and we shouldn’t be taking them away from their job.
No Shadowlands inhabitants should ever be an Allied Race.
no because they made them ugly on purpose because reasons i’m not petty enough to understand
and this
I hope San’layn becomes playable on Blood Elves. So Far the Venthyr is ok. But San’layn were better from Wrath.
Yes please, horde too.
They look pretty average.
The model also has a unique skeleton that doesn’t fit with all the cloth.
Not going to put anyone down for wanting Venthyr. Though I will say I’m not interested in them myself, personally, and would way rather have San’layn. Their lore is far more interesting to me than Venthyr (and any afterlife race in general). I sincerely do not like Venthyr, nor their lore. I fell in love with the vampyr curse since seeing it in Wrath and was excited to see it expanded in Legion. If they added venthyr without any sign of the San’layn or their lore, I would be extremely disappointed. Also would not play one.
That said, both being added would be ok, I suppose. Perhaps San’layn as blood elf customization (with lore at lease, please, pitch-black/red eyes, bat-like ears, and fangs) and venthyr as an AR. I don’t really support afterlife races being playable, though. Feels off to me for reasons others have explained better. I’m just voicing my opinion on it and don’t feel like getting into an argument.
Good luck to venthyr fans who want them, I merely am not interested myself, nor do I support the idea of afterlife races being playable, since I would rather see Azeroth races getting love, like ogres, Sethrak, saurok, et cetra.
Edit: Though I do encourage anyone who wants anything playable to make a detailed thread & put together ideas and lore, regardless of how I personally feel on it. It’d gather more support than just ‘I want this playable’.
I like allied races, but the Venthyr are so… ugly.
Pretty much this.
From a lore perspective it would be difficult to have soul guides from the afterlife doing “Bring me 15 flying warp squirrel livers” tasks for Azerothian quest givers.
Let’s see how well this fact of yours ages when Blizz finds a reason for us to be able to play them by the end of the expac and you look like a fool for being so “matter of fact”. If blizz want sit to happen, it will happen. Even if they need to retcon lore
I think it might be workable if you, say, could permanently sacrifice a character to reroll as a SL Covenant, and be sent out on field duty (e.g. Draka filching papers from the Legion) or some such.
Unless our covenant gives us an option to ascend to the rave we pledged ourselves to in Shadowlands and get a free race change to that race with that specific character for completing the covenant campaign. A sort of horizontal promotion to the next plane. (Like Stenchboje said)
They actually aren’t. They’re a brand new animation rig.
The races of the Shadowlands were once mortals themselves, and as we can tell, they have petty squabbles of their own.
After all, the Shadowlands are infinite and the souls entering it are infinite as well. It’s been made clear that the armies of Azeroth are at an all-time low. That’s why we’re not bringing the Alliance and Horde into the Shadowlands. The covenants could absolutely spare a few willing souls to go down and join a faction of their choosing.
Spoilers
Especially seeing as how the Kyrian are now allowing the Forsworn to reintegrate with the population of Kyrian, even if they won’t do their job.
What happens when that machine breaks entirely?
I’d be cool with it but I don’t see why they couldn’t be cross faction.
Personally I’d prefer the vorkai - the dryad race of ardenweald.
Blizzard could give us a non bipedal race and I’m here for it.
Narratively it seems quite strange for a Race native to the Shadowlands would take interest in the mortal realm much as choosing a faction.
I’m quite curious if they develop an addiction to inflict pain and suffering on living thing after being cut off from their Anima Supply; similar to the Shadowlands Wildlife during the drought.
Out of Universe, they do have numerous interesting unique animations; with the unfortunate downside of being too skinny.