Others and I have created several threads about Nakalim and Awakening in general. Many of those are a good-hearted atempt to enhance things, that sadly, are broken and lore-breaking. Here's a part of the series.

Exerpts from https://www.games2gether.com/amplitude-studios/endless-space-2/forums/66-game-design/threads/34614-lore-of-awakening-damage-control-mild-to-radical-proposals-a-cheeky-attempt-at-megathread 

WHY THEY ARENT HUMAN/HUMANOID/MEZARI

13 minutes ago - In Endless Space 2
New posts in the Thread « NAKALIM - ANOTHER MEZARI OFFSHOT?- COINCIDENT? UPDATE2: DEV REPLY INSIDE » you have created in the Forum « General ».

• 1.3. ARE NAKALIM AND MEZARI RELATED? (https://www.games2gether.com/amplitude-studios/endless-space-2/forums/65-general/threads/34502-nakalim-another-mezari-offshot-coincident?page=1 )
  

UPDATE: It seems not, they cannot find Mezan ie are not in any way related to other humanoids.

PROPOSAL

• 2.1 Dehumanize Nakalim. I know it's late. but not too late THERE’S A PRECEDENT, link to https://www.artstation.com/artwork/2x3lkJ and others pictured below. Approx 5-6 arts (leader and intro) would need to be edited in light mode or all (10 at most) in hard mode case. They is definitely too many humans in space and this weird-Earth, is just problematic and plain silly. They claim to be born there so well...it's either way very silly to have alien-humans on alien-weird-earth that somehow larp as lumpenegyptians with liberia vs humanitarian aid mentality, all the while  enforcing caste system of pitchblacks ruling albinowhites. Turning themunambiguously nonhuman FIXES those PROBLEMS right away and makes them FEATURES.

Light mode edits: Nose not-visible, no ears(cartrilage), no external lips - as pictured in upper left and lower right. 

IMHO those 4 look definitely better than anything else of Nakalim, as of now. 

Hard mode: more changes to make them less human. Elongating built(females already have long necks), removing breasts (weirdly many races have them), changing number of fingers and toes, removing toenails etc.

Light mode is quite easy and would take few hours tops, including changing intro. 

Further proofs:

Slowhands about humans in space:

https://www.games2gether.com/amplitude-studios/endless-space-2/forums/65-general/threads/33285-attempt-to-trace-the-history-and-timeline-of-the-united-empire?page=1#post-279803

Slowhands wrote:

(...)  Officially, the Endless Universe is what is referrred to as a "Second World" setting; Earth does not exist in the timeline.(...)

- The Mezari civilization has been around a long time (though not as old as the Endless), but its history is full of erratic ups and downs (civil war, invasion, over-expansion, etc.) so it never gained the power of the Endless. (...)

and 

https://www.games2gether.com/amplitude-studios/endless-space-2/forums/76-creations/threads/33206-my-mspaint-lore-chart-of-humans#post-279368

Slowhands wrote:

Okay, here we go with a few clarifications:

(...)
- The Mezari are the root of all spacefaring humanoid races in the galaxy. I use "spacefaring" to distinguish them from those native to Auriga (ed. mine - that are speculated to be Endless-derivative)

 (...)
 - To clarify the Mezan / Raian question:

The ancestral origin of all spacefaring ES2 humanoid races is indeed Mezan. However, there were several major exoduses... exodusses... exodi... whatever. The Vaulters were part of an earlier one, and the UE part of a later one.(...)

So there you have it - logically, if Mezan is the homeworld, and Sobra is the homeworld of Nakalim (as is stated expicitly in Awakening) - there's no relation. 

If Vaulters are the early goers, and they changed so-little through ages of genetic research and constant struggle, Nakalim would not change - when they are scientifically illiterate and there's no struggle in their evolution.

Their not only similarity to Mezari ie humans, but full-on human appearance is just cheap and/or an oversight that bids removing.

A confrimation from Dev, that Nakalim WeirdEarth is being fixed. 

The-Cat-o-Nine-Tales wrote:

For those who have not heard yet, the Sobra texture and art are going to be replaced in an upcoming patch.