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.
Yeah, I was legitimately creeped out by Marie Rose and Honoka when they were added to DOA5. It felt like such an escalation from DOA's traditional
"woah boobies" sort of horniness to something that was too icky to be funny anymore. From what I understand, they also just immediately skyrocketed in popularity in Japan, instantly eclipsing old series regulars.
There's probably something to be said about how otaku tastes had changed so much from the late 90s and early 2000s into the mid-2010s that DOA's big-boobed pro wrestlers and ninjas didn't cut it anymore so Tecmo had to add moeblob children to keep up
Soul Calibur and most other fighters don't sexualise all of their female characters to the same degree. They have their designated sexy characters like Ivy Valentine or Mai Shiranui, but in DOA every female character is blatantly intended to be ogled. Sexy pinups of the female roster in bikinis were a big part of DOA2's marketing which is probably why they redacted the ages outside of Japan.
I sometimes have trouble clearing the arcade ladders on normal difficulty so I would presumably get turned to paste
I mean like I said in my reply to the parent, I just dont process Marie Rose as a child lmao. I'm always blindsided when I see this discourse.
Yeah I didnt process original Ashley as a child either, and in that case I was right because she was always canonically 20 lmao. I do prefer the remake changes though.
I do agree that theres a trend worth noting I guess, that the coomer stuff was originally characters that looked like Kasumi and now is characters that looke like Marie Rose. I just... wouldnt have noticed it that way because my brain doesnt process her that way. Namco is probably intentionally baiting for that though. I just didnt think of it. So it confuses me. Subjective experiances I guess.
Yeah. Guess I'm losing the macro implications in the jungle of my micro experience with it.