What things will this entail, and I think that Charlotte of Naples will be considered a suitable bride for the young Charles d'Anjou?
Rene II was Duke of Lorraine NOT Anjou. Charles was the one to inherit the Duchy of Anjou at the death of his uncle (and Rene II’s grandfather)…
Consequences would be interesting as Jeanne would inherit Lorraine from her brother and later Bar from her mother.
Still the birth of a son to Charles and Jeanne is a big game change as Rene III not only would inherit the whole patrimony of the Anjous (Anjou, Maine, Guise, Lorraine, Bar, Provence) but also their claim to Aragon, Naples and Jerusalem (butterflying the OTL Italian wars as Louis XI and Charles VIII would NOT inherit the Anjou claim on Naples from Charles IV here). While Charlotte lived in France, I doubt who her father would agree to her marriage to the rival claimant to his family‘s crown (not who Charlotte had any claim of her own as female were usually passed over in Naples and Charlotte was a daughter of a second son with living (half-)brother(s) but still I doubt who Anne de Beaujeu or Charles VIII would give her to the Duke of Lorraine and Bar, Duke of Anjou and Count of Maine and Provence).
A far likelier match for Rene III if both his parents lived until he was old enough to rule would be a daughter of Mary of Burgundy (if she lived) or Anne of Brittany
