i'm admittedly not the most knowledgeable on japanese naming but iirc most of them are name readings and kanjis for the names in the game are pretty common. with the definite exceptions of kohane & emu (the former is also acknowledged in-universe as a rare name)? there are some names that, anecdotally, seem more common in fiction than in real life, though (shizuku & kanade mainly come to mind.)
as for readings… kohane and emu again simply because they're rare in the first place, but them being in hiragana is even weirder.
ichika (一歌, one song) does feel like a less common reading as opposed to, let's say, 一花 (one flower) or 一香 (one fragance). mafuyu being in hiragana (まふゆ) is also a pretty weird spelling of the name (you'd expect it to be more like the actual word, 真冬, midwinter/true winter). similarly, i'm pretty sure there are more common readings for touya (as opposed to 冬弥, expanding winter). but it's not like any of these kanji uses are weird or out of field by any means.
one that i'm pretty sure is weird is ena (絵名). i'm not sure how common "ena" as a reading is (sounds very modern tbh? most names with two morae kinda are like that though), but i definitely don't thing 名 is a common kanji for given names considering it. literally means "name" lol (granted it can also mean "fame" or smth iirc? which definitely makes ena's name both fitting and ironic)
i think all the other names are relatively common. and while i'm not sure about specific popularity of the actual kanji combinations, none of them seem outrageous enough to make me raise an eyebrow. which kinda makes sense. tbh most of the "weirdness" in pjsk's names comes from the surnames imo, and even then they're not names that would make you weirded by any means as opposed to, let's say, danganronpa lol
yeah there's an early area convo with an and kohane where an says kohane is a fairly unusual and kohane says her dad picks out weird names.
ichika is definitely a odd reading for the name but again this one is intentional and brought up in-universe that ichika's parents named her such because they met over a specific song they both liked. we know mafuyu was named for midwinter however the fact it's written in hiragana has the out of universe explanation for it not having any meaning. akito is also a kinda weird one i think afaik it's wayyy more common to spell it with aki for autumn.
when i was going through trying to find statistics for first names i went through changing my search terms with various character names and ena was one that popped up with the character overwhelmingly more than any real life examples of the name. again her name was pretty intentional wrt the kanji readings (painting name. lol). so many anime characters have pun/meaningful names.
out of curiousity i just put every name into search to see what came up, and the results were pretty much overwhelmingly the sekai characters all around. exceptions were haruka (several famous people with the same name), an (apricots, some people with the same name), minori (minori suzuki was actually the first result, plus a few other celebrities), shizuku (pictures of raindrops), and rui (stuff related to animal classification). shizuku and minori were kinda spammed with character art and links after a little while but haruan both brought up far far far more celebrity photos and websites (and apricots) then card arts/wiki articles related to the character. rui was mostly animal classification stuff and birds but then i got yaoi flashbanged.
kanade brought up another character and some music related stuff, ichika managed to pull up a chinese streamer, saki a golfer, shiho, airi, nene and honami a few social media accounts and a couple celebrities (and wuwa for honami bc it's got a location called honami city), akito and mizuki brought up pro wrestlers. mafuyu brought up a vtuber and tsukasa brought up some other characters from different franchises. most of these were still majority related to the character in search results, and everyone else was Just the character.
all that said search was really insistent on showing me unrelated bullshit and ai generated pixiv art and barely anything else even after switching regions so it might not be accurate to if someone else searched the characters. like i really feel like 司 should have summoned the enstars guy but it didn't just some other guy.
