I don't have much to go off, but I encountered this a few years back (maybe 2 or so). I believe it's fantasy.
I think the MC was teletransported into the world and ended up with a 'king' of sorts, she was like 16/17 or smth like that (I remember the shock jjsj). They had a bunch of kids, like 12, and each one had a 'power' or an area the excelled in. I think it was also a duty or a prophecy they had to fullfil (having that many children). That's all I remember from the plot.
BUT what I remember with 100% certainty is that, in the translation, the kids names were numbers but in french. So, first-born=un, second=deux, and so on.....