An update on the Hell Verse scan apparently 多重世界 refers to
the Everett many-worlds interpretations (aka multiverse theory). If you google "多重世界" it takes you to the Japanese wiki page on multiverse theory (which was brought to my attention when I posted a question on the r/translator reddit page inquiring about how it's commonly used contextually).
Hell being called 多重世界 (which is in direct reference to multiverse theory) debunks the notion that the original universe (pre Soul King) was only universal in size, since it would be housing a 2-C construct.
So I guess the most accurate translation of 地獄は、様相の異なる幾つかの階層からなる ″多重世界″ would be: Hell is, consisting of several layers/hierarchies of varying aspects/phases, a "multiverse".
Edit: Funny enough I was thinking on this Movie 4 Ichigo (Full Hollow and Skull-Clad) are arguably above the entire verse.
Reason being, if you give Yhwach the benefit of destroying SS and WotL = destroying two separate universal time-spaces, Bleach God Tiers in the manga would scale to arbitrarily above a 2-C structure composed of 2 universes. While if you give Movie 4 Ichigo the benefit of Hell being a reference to multiverse theory meaning a 2-C structure instead of multiple 3-A structures, since Movie 4 Ichigo is a threat to the entirety of Hell and he ended up destroying 3 layers (universes in this case), he'd scale arbitrarily above a 2-C structure composed of 3-5 universes.
Of course if you say that Aizen's statement regarding Mugetsu was literal and that Yhwach equated it to TS Ichigo, you'd have 5D = Mugetsu = TS Ichigo < the other God Tiers and Ichigo's stronger forms, and that'd be the absolute peak of Bleach strength.
Which is just weird cuz that means that Hell Verse FH Ichigo solos TB HoS Ichigo lol. However, either way you cut it, Hell being described with the many-worlds interpretations puts Hell Verse Ichigo among the God Tiers of the verse (something about non-canon forms scaling to/above the God Tiers lol, looking at you Quincy Ichigo, 5th Anni Ichigo, and now Hell Verse Ichigo).