Dare to DM

I flipped a coin (i’m genderfluid) and ended up with alexios, who i now prefer the voice acting of despite common consensus

I picked Kassandra.

I told myself I'd play Alexios on my second play through, but I didn't really like that game enough to play it again. It was too big and bloated for my taste.

None of the standard races in any version of D&D are constructs like androids. So for this concept, you would need to find a DM who is running a game that supports this.

But assuming they are cool with it, I would probably go with a Warforged Barbarian.

Warforged are a race of sentient constructs that used to be mindless automatons until there was a miraculous breakthrough in the process of their creation. They are made from things like wood and metal, and can fit into a high fantasy system.

I asked because i got into roleplaying stuff with tumblr’s roleplay scene so i’m kinda used to playing characters i create or know

That's cool! I'm not personally familiar with the roleplaying scene on tumblr, so I can't say I know what the conventions are!

It depends on the group and the DM. Some people might be totally fine with it, for others it might detract from the experience.

It's good etiquette to try and match the tone of the campaign you're in. So if the DM is trying to run a super serious high fantasy campaign, it's not cool to pitch Spongebob Squarepants as a character concept.

So he’s a mercenary who fights with bows and swords, and stealths around and takes enemies out silently when those don’t work

I know nothing of dnd so i was wondering if that’d be a possible to make character in it’s systems

Sure, that's possible! I'm going to keep my answer kind of general since I don't know what version of D&D you want to play, but all of them support this kind of thing.

The most obvious choice for this kind of build would probably be a rogue. They get something called "sneak attack" which does extra damage when you're undetected by your opponent. They don't always get all the weapon proficiencies that you listed, but any rogue can at least use a short sword and a crossbow. And if you aren't picky about race, most versions of D&D give elves automatic proficiency with the bow.

But there are definitely other ways to tackle it!

Ranger would probably be the route I would go. They don't get "sneak attack" damage like rogues do, but they're generally better fighters. And they still get the stealth skill as well as access to magic that can help, especially with things like tracking down enemies. Also, a ranger could have a bird companion that helps with scouting, just like Alexios.

Finally, the fighter class could be a good bet as well. Fighters get access to a variety of abilities that make them good with many weapons. The only downside of fighter is that they typically aren't very good at stealth. However, depending on which version of D&D you are playing, there are definitely customization options you could pick that would get you closer to what you're looking for.