Transfer Questions

I have a few questions about hombrewed wii to wii u transfer.I got homebrew channel on wii through smashstack and am scared it might not work.
(I dont have stuff like bootmii or dvdx installed.)

*Is it safe and will it work? If I get rid of the homebrew channel before transfer it will transfer the data right, with no problems?

*Will transferring from a wii that had homebrew void the warranty of the Wii U? I installed software on wii not wii u.

Thanks.

i have 2 wii u's. how can i transfer my saved file from one wii u to another?

I'm pretty certain the transfer software works just fine, even with HBC still installed. It'll only transfer official software anyway, and ignore anything else. It also shouldn't affect the warranty of the WiiU, seeing as you aren't doing any unauthorized on the WiiU itself.