As a kid I assumed no one knew how old these two were because they were mysterious ninjas, but it turns out Tecmo just redacted their ages in the English translation for obvious reasons. It's funny they went with this route instead of just bumping both characters up to 18 years old. I guess Tomonobu Itagaki refused to tamper with the sanctity of his precious DOA canon 
spoiler
I'm sad to report the PS2 version of DOA2 seems to be one of those early PS2 games that's interlaced to hell and back and will look like a jagged mess no matter how much you upscale it in PCSX2 
sad thing is those characters don't act or particularly look like children so that was better than the "she's totally 18 you guys" lolis that koei added in doa 6 and late doa 5 versions.
on the other hand, soul calibur is honest about talim and amy being children but it hasn't stopped the perverts. same with other fighters with "little girl" characters.
btw if you want to play doa 2 against people there's a small community on fightcade since the dreamcast emulator has rollback.
Is this about Marie Rose? She's the only character I can think of that could be read like this? Idk if thats the intent or not but Marie Rose just looks like a petite adult woman to me, 18-20. Should could pass for younger but I just... dont process things that way lmao? I've never been able to with Japanese media characters people say "look underage" unless they literally look pre or very early pubescent. Just not something that processes in my brain.
Like you mention Talim as well, with Talim I was surprised when I learned her age lmao. I again processed her as a petite adult (though I was myself younger than 15 when I played SC2 lol). Amy I suppose looks her canon age though even though I hadn't thought of it before.
Same with Street Fighter Lily as well. I''ve seen so much "she looks underage' discourse and I'm just like what? She just looks petite. Adults can be petite? And in her case there's no canon information otherwise.
Idk maybe I just have something broken in my brain because everyone says this lmao.
This isnt even a "please let me goon to these characters in peace" thing lmao I dont care about that. I just find the common perception around them odd because thats just not how my brain processes them.
Yeah, it's always seemed weird to me how characters that are canonically like 18-20 often get drawn in a way that scans as "30 or so" for me, and then characters that look roughly college aged are canonically 14-16. It feels like the animation equivalent of like live action high school dramas where all the actors are at least in their mid twenties.
I'm glad I'm not alone on this lmao.
I was just thinking about this some more and how characters are being drawn in what I'm currently reading (ZOM 100), when I reached a great character recap spread at the start of volume 10. For the fun of it, I want everyone to look at this version with the ages and bios censored and try to put an age to each character, weighing both anime tropes and the context of this conversation and how the characters scan in a vacuum:
Hint:
The three guys on the right are all the same age, and the girl on the left is the oldest character out of all of them.The uncensored image (mild story spoilers):