bugoy, i think he's wondering if he installs it onto the body like how the ovation guitars have the forward button mounted.
answer... it shouldnt. its possible... but it shouldnt affect the tone.
but my question is... why would you want to put a strap on a soprano? theyre so small and light, that you really dont need a strap for them. even on my tenors, i have strap buttons, but i have grown to love the feel of having the uke free. of course, for some solos, it is easier to do with a strap. but most of the time youre not going to be doing too many solos on a soprano that are too complicated, since the neck is so short. IMO a strap on a soprano would be more of a hindrance than an asset, just because of how small they are.