You can't enhance terpenes with adulterants. That would simply be adding flavors, which may or may not alter the overall flavor or scent, but the terpenes would be unaffected. That's genetics and response to environment. If putting stuff in the ground made weed taste like the stuff you're putting in the ground, my weed would taste like bat shit and seaweed.(It doesn't. My last harvest tastes like Pina colada.)
Since you're not changing the terpene profile, just the flavor/scent (doubtful, but let's just assume so for the sake of argument,) there would be no change in effect on the user.
It was probably mentioned already, but, mangoes and lemon grass don't work. They're also junk science.(Their effect enhancing effect, I mean.)
But seriously OP, if you're interested in something better grounded in objective science, but still completely hypothetical, check out my little article on insect herbivory impacting terpene production. On my facebook.
Again, it's likely not a feasible way to enhance a terpene profile, but it's better than putting oil in your water.