Charles will stay childless as OTL?
Anne Marie of Orleans or one of the Neuburg girls for Charles William and/or James Frederick can work if they will marry Catholics or some protestant girls (need to find again the usual list), an heiress for Alexander Robert
As always I will push for Catholics matches for the York princesses (the Great Dauphin for Elisabeth and Peter II of Portugal for Amalia) because Charles II's politics and James interest were all in that direction
(Louise Henrietta can work for Joseph I as she would be likely of the same age of his OTL wife or as usual one of Leopold daughters by Claudia Felicitas can be born as boy and survive)
Hmm interesting, I'd say Amalia could marry either Peter II or a son of Peter and his first wife. CHarles William marrying a Neuberg girl works for me, or if Charles II has a daughter, perhaps they'd go for Charles William and the daughter marrying one another? Alexander Robert to Anne Percy seems good for me.