I just completed a system transfer from a homebrew-enabled Wii. I'll provide what details I can. Relatively speaking, this was a lightly-used Wii with lightly-used homebrew. I didn't have much to lose if the process happened to fuck up my soft-modded system, so I figured I might as well be the guinea pig for GAF.
My Wii system details:
- Wii system menu 4.3 (latest version)
- Wii Shop version 21 (latest version, released about a week or two ago, required for system transfer)
- Homebrew Channel (latest version, updated it last night in preparation)
- BootMii version 1.3 (installed to boot2)
- Riivolution patching app (only homebrew app I still have; I basically just used it for custom TvC soundtracks)
Transfer process details:
- Everything that can be transferred will be transferred. You can't pick and choose, and you can't move or copy games back to the original Wii system after you complete the process because the content licenses will be moved to your new Wii U console. Save files that aren't locked to the system can still be moved around freely and copied back to your old system.
- The transfer process seems to ignore homebrew applications entirely. Not only was the Homebrew Channel not transferred (as should be expected), it remains intact on my original system. BootMii still seems to function as normal. I can still launch the one homebrew app I have and it appears to work fine.
- System-locked save files (such as Super Smash Bros Brawl) WILL be transferred, and it will now be locked to your new Wii U. If Gamecube controller ports are important to you, this may be a point worth considering. If you are capable of stripping out the system-lock on the original save via homebrew, I recommend trying that and then saving a backup copy of the save file on an SD card, then copying it back to your original Wii after the transfer process completes. Not sure if it would work, or if the transfer process would ignore tampered save files entirely, but it's worth a shot if that's important to you.
- Save files from imported Wii games WILL be transferred. My save file for the JP version of Sin & Punishment 2 made the jump.