Basically the mashup / texture packs are missing some colors from the original console edition (xbox one or otherwise). They were stored in a .col file which is a binary file type they used for the game. I made it readable for you guys to see.

What I have seen so far since they converted TU > Bedrock edition:
broken sky
broken particles
all or almost all colors from the TU .col files are missing
different music compared to TU? Please confirm as it's difficult to get ahold of TU encrypted files
I would also check the textures themselves between the old atlas's and current bedrock edition. Because if everything else doesn't seem fine why would the textures. Hash each file and then compare them