Ok Thanks, will take a look.

Mount and Blade 2 plays in a pseudo medieval eastern Roman empire.

Rise and Fall: Civilizations at War aso featured the Romans. I think it was eventually turned into a freeware game.

The Elder Scrolls games: Imperials are the dominant race. Their armour and culture is similar to that of the Roman Empire.

Mass Effect: Turians are loosely based off of ancient Romans. If you don't believe me, a clue is in the name. (cen)Turians.

The Asterix series of games, as you get to fight Romans, instead of playing as them...

I'll give you Elder Scrolls that's very much Roman.
But Mass Effect Turians, not even close. That's the name of their Species not world.
But that wasn't even the question on point.

From the Mass Effect wiki:

Turian is based on the word centurion. Palaven is based on Palatine Hill, as well as the word "paladin." Turian names, culture, and military doctrine also mirror that of the Roman Empire, especially their emphasis on colonizing enemies.

https://masseffect.fandom.com/wiki/Turian#Trivia

Maybe OP was interested in games about the Roman Empire not simply inspired by it.

Because Ancient Romans didn't speak Italian...? You may as well ask how they can make the game without including Traditional Chinese.

There's some mystical, magical, legendary but ethereal technology called SUBTITLES ???
For when you want to narrate in Latin or Traditional Chinese. But that's just me thinking.

Some of the Settlers games have a Roman faction.

I haven't played https://www.gog.com/en/game/empire_earth_gold_edition but reportedly the expansion pack added an Ancient Rome campaign.

Honourable mention: the Romun Empire in the Ys series.

Unfortunately, that's not how this works.

GOG can only add titles, for which they get the distributing rights from the developers/publishers.
And most of these are hesitant to release their (newer) games here, because one of the (and maybe THE) main requirements of games that get released here, is the lack of any DRM (Digital Rights Management).

(I personally don't believe in it, but) if you want to feel like you actively did something to get (a) game(s) here, you can always vote for it/them on the Community Wishlist:
https://www.gog.com/wishlist/games

https://www.gog.com/wishlist/games/total_war_rome_ii + https://www.gog.com/wishlist/games/total_war_attila
https://www.gog.com/wishlist/games/grand_ages_rome_gold
https://www.gog.com/wishlist/games/ryse_son_of_rome
https://www.gog.com/wishlist/games/imperivm_great_battles_of_rome
https://www.gog.com/wishlist/games/shieldwall_chronicles_swords_of_the_north
[We are Legion: Rome - not yet released]
https://www.gog.com/wishlist/games/total_war_saga_troy or https://www.gog.com/wishlist/games/imperiums_troy_2020

Hello and thank you very much for the detailed reply with the possibility to vote for game titles. I have voted for more than one title e.g. Total War with the historical dlc on the Roman Empire. It is a fair method to contribute with votes with the hope that GOG will be able to evaluate and make decisions on community requests.

Rome ad 92 (Rome: Pathway to Power)

I would like to add a thought, because over the years we have noticed fewer projects in the PC gaming video field where they embrace the history of ancient Rome. That's just my opinion, perhaps the external demand was for games such as shoot-em-ups where the strong point is shoot 'em up and lots of blood. The general market has other priorities of accepting more action and frenzy games by lowering the historical-cultural-artistic part. Although I must say that GOG has added an excellent title: Kingdom come Deliverance. A lot of criticism but a unique historicity. I tried the game for many hours and was amazed at the many details that were created. Medieval setting. I read somewhere that it was also used in a university to teach students how people lived in that historical period, etc.