Can i use xenforo 2 add-ons with xenforo 1.5.x?

There are new add-ons exclusive for xenforo 2. And the thing is i don't have the new version of the theme that i'm currently using. It would be great if its possible. I don't want to spend my money on an add-on that i can't use.

You can try ?
If it don't work, restore a backup

NO, XF2 Addons will not work on XF1 at all! And yes it's annoying having to buy the addons all over again.