thanks @Izhido_XR for the prompt response.
May be I am doing something wrong, but the below code snipper from the official swift doc is working fine when the run destination is set to Mac, but when I change the run destination to Apple Vision Pro, it doesn't compile and throws some errors.
let cxxString = std.string("This is a C++ string")
let swiftString = String(cxxString)
No exact matches in call to initializer
So, what I get from this is that the mixing Swift and C++ doesn't support visionOS for now.