Store model with relations in one method in Laravel

It is possible in Laravel to store JSON for a new model with relation models (existing or new) in one save()/create() method?

For example:

{
    "name": "Name of new Model A record",
    ...
    "comments": [
        {
            "id": 123, # ID of existing record of Model B
        },
        {
            "name": "Create new Model B record"
        }
    ]
}

Code for writing:

ModelA::create([
  "name" => "Name of...",
  "comments" => [
    ["id" => 123],
    ["name" => "Create new..."],
  ],
]);

Method ModelA::create()/ModelA::save() write to database just record of Model A. Record of ModelB not created.

Any errors.

Relations in models are correct.

P.S. I using UUID as primary and foreign keys.