Transfer "save data" from Wii-mode to "Wii U-mode"
No. The answer is No. The VC games on the Wii U can not access the save game data of VC games within the Wii-mode environment and vice versa.
The VC game save data for games in Wii-mode can only be accessed by the VC games in Wii-mode.
So you'll need to restart your saves from scratch when you play the new Wii U VC copy.