For Legacy DLCs from TSW3, do the pak files change? Can I copy the pak files from the TSW3 DLC directory to the TSW4 DLC directory and then verify the files in TSW4? Would save 200Gb of download time.
The DLC files do change. You can try copying the files and verifying, so Steam will try to download only the differences. The thing is that if a file is too different Steam might decide to download it all anyway. Also, if any of the files has a different name Steam will download it again and not remove the old one. In this case, it can cause any kind of side effect, including crashes or game not behaving as expected. Also keep in mind that old DLC is not being released for TSW4 until the 26th, so Steam will not try to update those files until then. If you place the old files in the DLC folder before then I bet the game will not be happy. TL;DR: Might work, but try it at your own risk. If you experience any kind of trouble while playing the game, the only way to make sure it is not a side effect of the unconventional installation process will be to reinstall everything the standard way.
So for example moving a .pak files from TSW3 Epic Version to TSW4 Steam version won't work and the game won't recognize it ? Because it worked between TSW3 Epic to TSW3 Steam.
