Yes, if the character is not present in the preview image that shows all the characters in the project description, it will not be in any of the fonts.
Viewing post in Pixel Font Megapack - 175 Fonts comments
It’s a lot of work but that doesn’t mean it’s not worth it. If there is high enough demand I will do it, but the fonts have to be a bit more profitable than they currently are for me to afford too much of my time on them.
Ultimately, tho, my stance is that the more languages I can support, the better! I just have to juggle many projects right now and have to be careful with my energy. Hopefully I can eventually extend them.