Tried it on my Note II CM11 based Rom.
Would not install as APK but of course was able to flash. However it sort of hangs. I can select the Launcher 3 from settings but then it just stays there. No Home actually comes up. It just hangs. Have to go back to settings and change to Google Home and everything works. Not sure why.
Okay: Update. Wanted to give it a closer look why it did not work and found the following.
Managed to fix it. The issue is that even if you install/place Launcher3, you *might* still have a launcher3.odex file lingering around from your previous install of Launcher3. This causes it to hang.
Go into priv-app and delete that file and then if you wish launcher3.apk as well as the *.odex, then install or place the new one. You should not have to but if you feel inclined, REBOOT and you should be good to go.