Blu-ray

4K restoration from Original Camera Negative

Not sure about foriegn

Popeye was mixed for a failed Vistasonic system with 4 discrete tracks (L/C/R/S). That mix has never been released on home video in its original form.

The older 5.1 track appearing on older DVD/BD releases sounds excellent. It appears to be a slight upmix of the original mix, only splitting the surrounds and adding LFE. It sounds close to the old analog LaserDisc, which is likely the original mix in a matrixed form.

The 5.1 included on the UHD is a new remix which significantly differs from previous tracks. There are new foley effects all over the place. Music is jarringly spliced in from different sources. Unlike the old 5.1 which had clearly discrete surrounds, the channels surrounds overlap somewhat with the fronts here.

Details on the new mix from Paramount's former head of restoration: https://youtu.be/P-AmjqViJyE?t=788

The 2.0 tracks on all DVDs/BDs are just downmixes of their respective 5.1 mixes.

Samples

Sony Blu-ray uses a newer 4K master than Indicator and is noticeably better see caps

Though note its different color grading from the IP-sourced but poorly compressed Fun City Editions US Blu-ray (caps)

Judging from spectrograms at https://forum.blu-ray.com/showpost.php?p=23933756&postcount=57, Fun City Editions US Blu-ray appears to have marginally less filtering than Radiance 4K Blu-ray (whose padded 16-bit depth is a non-issue). There are also loudness differences, though it's unclear whether dynamic range also differs. Caveat: need to A/B both tracks to confirm, but no one has posted actual A/B impressions.

Identical. Arrow 4K Blu-ray is lossy transcode.

BFI Blu-ray renders grain structure better than Severin 4K Blu-ray’s disappointing encode, although Severin does feature an HDR grading with Dolby Vision. Furthermore, Severin’s soundtrack is worse due to the noise reduction applied.

Severin 4K Blu-ray has very good extras that are more relevant to the film

Paramount 4K Blu-ray captures more grain in image 6&24, but Shout! Factory Blu-ray is very good see caps

However it seems like the Britain Fox Blu-ray is slightly cropped see caps

Shout! Factory Blu-ray new 2K scan supervised by Penelope Spheeris