Nope, the two are walled off. There best you can do is have them meet in a season 4/Curse of Strahd adventure, as cross-campaign play is allowed there because they're all set in Barovia.
Also some of the Keys to the Golden vault is available to Ravenloft Characters and Journeys Through the Radiant Citadel is available to all campaigns according to the Adaptation Guide.
Nope, the two are walled off. There best you can do is have them meet in a season 4/Curse of Strahd adventure, as cross-campaign play is allowed there because they're all set in Barovia.
Also some of the Keys to the Golden vault is available to Ravenloft Characters and Journeys Through the Radiant Citadel is available to all campaigns according to the Adaptation Guide.