Honestly i dont know if these have any romance in them yet, cause i havent read their novels ( if they have any novels) but heres the one i enjoy so far, there arent any romance with the mc and the female chara but they seems just thirsting for the mc (so far as i read it though) so i didnt really think of that as romance, but still if you're interested
Raising Villains the Right Way
The S-Classes That I Raised
Ranker who lives a second time
The 18-Year Old Demon King
Omniscient Reader's Viewpoint
I’m Not That Kind of Talent
The Evil Ring
Special Civil Servant

I really hope i my feeling was right about there'll no be romance in this but i was wrong, i thought it'll be my long waiting favorite fantasy manhwa with no romance what so ever, but noo. I was liking it so far without the romance until the latest chpter.... will there ever be a good fantasy manhwa with no romance thats just as good huhuu, i even dropped solo leveling because of the reason....