The LittleBigPlanet mashup pack cannot be used in Minecraft Preview for PS4 or PS5. Which does not make sense since it should always be usable on a PlayStation console, no matter what version of the game it is. This applies to the skins included with the pack as well, they revert to a default skin when trying to use them in preview.
MCPE-186473
LittleBigPlanet mashup pack is unusable in PS4 and PS5 preview versions.
Resolved
Cannot Reproduce
0
This seems to have been fixed as of 1.21.40.25. The skins are now usable in both preview versions.