The newer season of Bleach chooses very interesting kanjis for the ending poems
For example in this episode's poem:
天(そら)に響めく(どよめく) まやかしの
捉う心(とらうこころ)にはしる旋律(せんりつ)
For me it's interesting that the kanji used for そら (sky/heaven) is not the usual 空 but 天 which is never read そら, usually read てん, but it conveys the meaning of heaven more than 空.
I've seen Bleach doing it several times in the poems
Yeah, it's uncommon, but I've seen that そら reading used in other places too, but it's mainly been in manga, anime, videogames, like in your example.
I wonder if it was a relatively recent fad to read it that way (like in the past 20 years or so?)
In the visual novel 9-episode, there's a kind of a meta comment about that unusual reading.
One of the characters in the visual novel is a teenage girl who was born with the 天 name and そら reading. She intensely hates this name because because everyone usually just calls her てん instead of そら. She describes her name as a 厨二ネーム and she blames her parents for trying to be too edgy, like a 厨二病 teenager edge-lord who has read too much manga and comes up with cringe-worthy names thinking they are cool-sounding but they are not.
Because of that 厨二ネーム, she thinks that's the reason why she's grown up with an eccentric personality, and does strange goofy things, all because of the edge-lord-sounding name. She vows that when she becomes an adult, she'll change her name to something more conventional.
The 9-episode visual novel came out a few years ago, so the girl's parents might have grown up reading manga like Bleach. so I wondered if this was a kind of meta-joke on chuuni-souding names with weird readings.
I laughed when I read the teenage girl's rant about her name because 厨二病 is something you usually attach to teenagers, but here, the teenager is criticizing her adult parents for being like that, so it's a kind of role-reversal.
A bit related to that, I heard that you are restricted on what kanjis to use for names but not on how they would be read. So a person could be named 空 and have the reading be スカイ(sky)
I didn't know about the kanji restriction but that makes sense.
As far as readings, yeah, you'll definitely see some wacky ones. There's also a lot names that use ateji and spell things phonetically with kanji like 真理亜 (Maria).