Triplanar? You want to apply textures on all three axis? How will you know which one to use? The normal? I mean, you could try it. You’ve got nothing to lose at this point I think.
I’ll provide some math tips for you if you’re interested. So you’ll need the normal in local space. Then compare with each of (1,0,0), (0,1,0) and (0,01). You do this by taking the dot product of your normal and one of these vectors. Do this for all three. The one that has the highest absolute value (abs node) is the planar projection you want to use (or you can blend). So you grab the Position in local space (you may have to take the world position and transform it to local space) and take the two coordinates for the plane you’re projecting and form a UV coordinate based on the distance from the origin of the object and its size.
Good luck! This isn’t straightforward to do. If you have a better idea, let me know and I’ll try to help if you need it.