Making a cool character idea work without homebrew

I have dmed the last couple of games I played and one of my players (who has no dm experience)has recently aproached me and offered to run a game  and for a while I have been sitting on an amazing character idea it comes from the 1981 ttrpg star frontiers wich was a sci fi game that had an alien race called the ossacar their whole thing was that they reproduced asexually so they were all clones of eachother so they each became experts in a different field to prove they were different I want to bring it to D&D but since it is my friends first time dming I don’t want to make their life harder with homebrew any ideas?(if it’s relevant we play 2014 D&D)

It kind of seems like you could skin almost any species like that. Though something like a warforged or autognome might be easiest. And warforged does get a free skill proficiency so that could be something to look at.
If you’re looking to be an expert at something, look at one of the many classes/subclasses that give you expertise in a skill or two.

Homebrewing literally exists to make things for your home game that don't exist premade in the rules. Not using 3rd party content is weird, but fine, but not using homebrew is misunderstanding how to play D&D... you're supposed to make up things for your game as a DM.

I have no idea where you got the idea of having a rule that the DM cannot make things for their own game, but you should probably start be reviewing that.

Quote from kirito34 >>

Homebrewing literally exists to make things for your home game that don't exist premade in the rules. Not using 3rd party content is weird, but fine, but not using homebrew is misunderstanding how to play D&D... you're supposed to make up things for your game as a DM.

I have no idea where you got the idea of having a rule that the DM cannot make things for their own game, but you should probably start be reviewing that.

They said in the OP that it's their first time DM'ing and they don't want to make things more complex for the DM. Creating a balanced new species could be tricky. It's not unreasonable to not want to add that to the plate of a new DM.

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As for the OP's question, it sounds like there's not a lot to build on for this species. You've got a bit of flavor: they reproduce asexually, so lacking gender, they may often use they/them pronouns.

Mechanically, the only things to hang a hat on is being an expert at something. This feature could be expressed as:

"Expertise: You gain Expertise in one skill you are proficient in."

Now throw in:

"Tool Proficiency: You gain proficiency in one set of Artisan's Tools of your choice, and one set of other tools of your choice. You have Expertise in two Tool Proficiencies of your choice."

(Note that you can only have Expertise in Tool proficiency under the 5e/2014 rules). However,  that doesn't feel like enough mechanics for a species. You'd need to invent more. And that invention is definitely something I would hesitate to toss onto the DM's stack.

Quote from Grungthebreed >>

I have dmed the last couple of games I played and one of my players (who has no dm experience)has recently aproached me and offered to run a game  and for a while I have been sitting on an amazing character idea it comes from the 1981 ttrpg star frontiers wich was a sci fi game that had an alien race called the ossacar their whole thing was that they reproduced asexually so they were all clones of eachother so they each became experts in a different field to prove they were different I want to bring it to D&D but since it is my friends first time dming I don’t want to make their life harder with homebrew any ideas?(if it’s relevant we play 2014 D&D)

In 2014 rules, reskinning a vedalken from the Ravnica book -- a species that essentially gets built-in personal guidance to aid their skill checks, as well as extra proficiencies -- might be your best bet

Tireless Precision

You are proficient in one of the following skills of your choice: Arcana, History, Investigation, Medicine, Performance, or Sleight of Hand. You are also proficient with one tool of your choice.

Whenever you make an ability check with the chosen skill or tool, roll a d4, and add the number rolled to the check’s total.

I had thought about the vedalkin but not too hard I think that’s what I will go with since it’s unlikely another player will also play one

Quote from Grungthebreed >>

I had thought about the vedalkin but not too hard I think that’s what I will go with since it’s unlikely another player will also play one

 It might be an interesting concept for everyone to play one. As if you are all from that species and each specializing in whatever that player is into. I don’t know what the dm is planning but it could be a fun way to run a campaign. Maybe you all showed up together in whatever landscape via: portal, spaceship, or spell….

That is a good idea and I would love to see that happen I will keep it in mind anyone who reads this if you actually do it please let me know how it turns out

"they each became experts in a different field "

I count 18 skills. 

Casters will be good at arcana

Martials will be good at athletic, acrobatics

Rogues will be good at stealth,sleight of hand

High cha builds will want persuasion, deception, performance

Clerics will take religion, medicine, and insight.

Druids will have survival and animal handling

Wizards will throw in history and nature

Everyone wants to be good at perception.

Which leaves.... Nothing... that will distinguish your character species from another charavter built using the same species and taking the same classes as you.

If you want to be proficient in a lot of things, go with the2024  warlock, take the lessons of the first ones->skilled origin feat over and over, and get proficient in a lot of things.

If you want expertise on some things, youre looking at rogue with a ranger dip.

Having played various skill monkey builds, i will say its often disappointing because skill checks outside combat are usually the sort of thing the dm wants you to succed at, to hook you into a story plot or to explain what you need to do next, so rolls and help and rerolls happen quite often until someone succeeds, meaning you having proficiency/expertise in history doesnt change much if you took perception instead and the whole party rolls history until someone succeeds.

And there are usually better things to spend your warlock invocations or spend your build multiclassing into something just for a skill.