I do not know what to say at this point, this bug still exists almost one year after its discovery.
Just noticed this issue today.
Noticed the same thing in my world today (Bedrock Realms).
Downloaded the world to both xbox and PC and the textures was reversed in both.
The world was previosly on an 1.18.12.1 server (dont remember client last version) before both client and server was upgraded, client to 1.18.31 and server 1.18.32