It seems unlikely, to be honest (although I can't definitively rule out a cunning trick).
There is no first-class identity for a given specialization (outside the type arguments that select it), to compare.
So, you could make it work with your own templates, if you want, but you can't write an ad-hoc inference for existing templates.
Consider also that it wouldn't work anyway, in the sense that it couldn't tell whether two instantiations have a compatible layout: even if Templ<int>
and Templ<char>
are instantiated from the same template code, with no specialization, that code can use traits classes which are specialied.