Android 5.0: Create link in internal storage to SD Card
There is an app called "Link2SD" on Google play store.
Link2SD uses a secondary partition on your SD card and uses it as another segment of internal storage.
Link2SD moves apk, dalvik-cache (.dex), lib and internal data files into this partition, which the OS mounts on boot, and creates a symbolic link in the original location.
This retains the file structure that the system expects but with the bulk of the data moved to the SD card.

Linking obb and external data folders of apps and games
- root permission
-Second partition on SD card is optional, folders can be moved to the 1st or 2nd second partition of the SD card.
Hope this works for u :)