Validating JSON schema with intersections and unions classes in Kotlin

I'm thinking about rewriting small web server project that I have from TypeScript to Kotlin. The problem that I have is server accepts a JSON with unions and intersections. For the purpose of this example:

• I want incoming JSON to have a string field with either the name one or name two, but not both or none of them, e.g. {"one": "some text"} or {"two": "some other text"}
• I want format of incoming request be dependent on one of its fields, e.g.:

{
  "someFlag": false, // or can be missing
  "ids": {
    "user": 123 // mandatory field for this structure
  }
}

or if someFlag exists and true, it makes couple more extra id fields mandatory

{
  "someFlag": true
  "ids": {
    "user": 123,
    "company": 456, // mandatory because someFlag is true
    "device": 789   // mandatory because someFlag is true
  }
}

Unions and intersections within same type is quite trivial in TS, but I have no idea how to achieve same thing in Kotlin and then utilize validated request in a typesafe manner. I'm pretty sure I can try to figure out some "dirty" approach with bunch of optional fields and manual checks for field existence on multiple program levels, but if there's a way to make it typesafe, I'd rather take it.

So the question is, can I make this validation typesafe?