From CiNEPHiLES:

Sources:
#1: JPN Blu-ray (2025) - video, 5.1 audio, subtitles (thanks TMT!)
#2: LaserDisc (1998) - original mono audio
#3: FRA Blu-ray (2017) - stereo audio, subtitles
#4: NTSC DVD (2000) - English dub
#5: JPN Blu-ray (2008) - commentary
#6: GBR Blu-ray (2013) - subtitles, named chapters
#7: GBR Blu-ray (2019) - subtitles
#8: ESP Blu-ray (2016) - subtitles
#9: GER Blu-ray (2016) - subtitles (thanks iFPD!)
#10: HKG Blu-ray (2023) - subtitles (thanks PTer!)
#11: TWN Blu-ray (2010) - subtitles
#12: MUBI WEB-DL - subtitles
#13: iTunes WEB-DL - subtitles
#14: Crunchyroll WEB-DL - subtitles

Video comparison:
JPN 2025 vs ITA 2024 vs GBR 2013 vs GBR 2019: https://slow.pics/c/wQQPUoJT

Audio:
Perfect Blue was theatrically released with a mono mix, due to budget constraints. This mix is only available on the 1998 LaserDisc release.
2013/2019 All the Anime/Shout! Factory releases include an 2.0 dual mono track (of incredibly low quality), but it’s a downmix of the stereo remix.

Home video releases were upgraded with new stereo and 5.1 remixes.

Stereo mix appears to differ from the mono more than the 5.1 track, with numerous differing sound effects, cue timing and ocassional other changes. For example, background dialogue played on the car radio around 43:50 is only present in this mix. The remix is only available on LaserDisc, old Japanese DVD, and surprisingly, the French Blu-ray. UHD instead offers a 5.1 downmix.

The 5.1 mix is the same on all Blu-rays, with the LaserDisc version differing only in extra channel bleed and compression.
Quality-wise, all discs are about the same, preferred 24-bit track from UHD.

English dub, as the 5.1 included on all discs is a poor (up)mix with tonnes of bleed, with Japanese 5.1 on the NTSC DVD where the dub originates, suffering from the same issues compared to other sources.

Subtitles:
English SRT subtitles from MUBI, due to proper formatting with appropriate line breaks and music notes.
English PGS subtitles from the 2013 GBR disc due to styling. Contents are the same between all options.

French web subtitles converted to SRT from ASS, as they were just plain subs without any typesetting.

Skipped subtitles from Italian Blu-ray/DVD as they have on-screen text hardcoded and missing from subtitle tracks.

update:
Copied metadata from wrong torrent page
Removed space from title