VPC Endpoints with VPC Peering: Not supported directly. You cannot access a VPC endpoint in another VPC through peering. Endpoints are only accessible from within the VPC (or VPCs connected via the same AWS PrivateLink).

VPC Endpoints with Transit Gateway: Supported. You can connect multiple VPCs to a Transit Gateway and use it to reach VPC endpoints, but only if the service supports Private Link and you configure the routes correctly.