Thande
Donor
Well, I'm not sure if it would be possible (is there anyone knowledgeable about the Hannoverians?), but I think such conversion a bit unlikely. By 1711 they haven't got the British throne yet, and they would receive it exactly because they were firmly Protestant. I'm not sure how having a so close relative converting to Catholicism would be seen in London.
Frankly, not well. Under those circumstances I think Parliament would tear up their invitations and go after the Hohenzollerns instead.