I'm not sure what quantifies a 'moe' look since I thought it was more about behavioral tropes of pitiableness, which '90s anime Hotaru already had out the wazoo (I have occasionally wondered if the linguistic meaning of the name "Tomoe" has anything to do with "moe", since everybody else was doing meaningful/pun names like "Rabbit of Moon" or Minako "of love"... for that matter, "Mina" is the word for "Everybody" and "-ko" is a female suffix, so is her name "Everygirl" basically? I'm not an expect on these things so I might be drawing the wrong connections).
That said, I feel like Sailor Moon has a strange relationship with age (even before getting into SuperS' themes). In the '90s anime I would say all the Inner Senshi look about 17 to 20 in most scenes, not 14.
Mamoru, Motoki, the Shitennou, and other comparable guys tend to also look 20-something, but be a bit taller than the 14 year olds like they were supposed to have the height gap difference that would imply, but the 14 year olds already look like grownups so it makes the guys (especially with their limb length) seem like enormous bodybuilder types.
Zoisite's height is inconsistent, but I definitely prefer the shots where he's way shorter than Kunzite, which would put him more comparable with the inners' height... which is to say, more like the approximate height of an average adult woman.
Sailor Pluto is obviously older, at least 25, but her limbs are crazy long and she looks kinda weird when I look at her too long, like she's been stretched out beyond human proportional ranges. Haruka and Michiru are slightly in that direction (and definitely don't look like teenagers), but not so severe (especially not Michiru).
Hotaru actually looked like a teenager usually. Except when she was a baby.
Chibi-usa starts off tiny and does actually look like a little kid. Then she gets way bigger as Sailor Chibi-Moon (I think it's a deliberate change, at least in the manga?) and looks Hotaru's size (but they aren't really seen together like that much and she's somehow shorter than Sailor Saturn in the few shots where it comes up, IIRC). But there's that weird shot in the second credits for SuperS where they have Chibi-usa back to back with Sailor Chibi Moon at the same height, and had to compromise (mostly by making Sailor Chibi Moon very short in that shot).
Chibi-Chibi looks like a super deformed UFO catcher come to life. Are we sure she doesn't have AA batteries hidden in her back? It might explain some things.
Rei's grandpa likewise is a characature beyond the point of seeming like the same species. I've seen this look a few other times, the tiny old people. But Mamoru could pick him up and hold him like a small child!
Umino is a weird case. In the manga he often looks like an unshaded, single-pass scribbly outline. In the anime he hews closer to human proportions, but is just a little bit off. His limbs always seem stubby, his face shape is different to accommodate his glasses (so is Princess Dia's in episode 22; her face changes shape a little when her glasses fall off), his ears re big circles and his hands are kinda abstracted and stubby. Everything about Umino is kinda stubbly, except his arm and leg length, which expands to be just slightly short of Naru and Usagi's (but there were enough goofy SD-esque shots in season 1 that they occasionally become very stubby themselves all of a sudden in certain shots, as opposed to the majority of shots where they are much more mature looking).
Basically, it seems to me like the logic they were using (for girls, anyway; guys defalt to being tall bishonen or weird charicatures) goes like this:
- The head size never changes much.
Toddlers (Chibi Chibi)- Tiny tiny limbs, smaller than babies. Absolutely enormous eyes that could fit both their tiny fists in a single eye.
Children (Chibi-usa in R)- Small limbs, but much more reasonable.
Older children (Stars Hotaru, Chibi-usa in SuperS)- Kinda long limbs, looking like teenagers. Eyes start to get slightly smaller.
Very young teenagers (S Hotaru)- Slightly longer limbs still, looking like mature teenagers for sure. Not too different yet, but then...
14 year olds (The Inner Senshi in season 1 and 2) - Long limbs and full breasts, look like adults. Eye size is still fairly big but reasonable.
16 year olds (Haruka and Michiru)- Longer limbs still, could not be mistaken for teenagers by anybody. Maybe lipstick. Eyes get smaller.
18 - 40 (Sailor Pluto, the Inners in the last scene of R)- Even longer limbs and definite lipstick (unless your name is Haruna Sakurada), you are too stretched out to pass for a regular human. Eyes get smaller still and are kind of thin even if they never were before.
40+ - You start getting wrinkles and look kinda ugly. (That snooty lonely rich lady with the soup in SuperS who yells at a cashier at the beginning.)
Old person (Rei's grandpa, probably some rando or something) - suddenly you are very stubby again. Perhaps your limbs became brittle and snapped off, or retreated like reverse bamboo shoots.
The problem for me as a fanartist is, wanting to draw these characters in their early 20s, I am strongly inclined to draw them similar to how they looked at 14 instead of making their limbs insanely long or giving them lipstick (I don't really like lips anyway).
In contrast, I think something like the Love Hina manga (not the anime; the anime was ugly) gets a more believable age range, with regard to characters age 12 to 20 looking their ages. But I think they were still going for generally a more sexy sort of look than cutesy, so mostly I would just say Sailor Moon makes everybody kinda stretched out.