workflow1.yaml

---
    chain:
        -
            name: "task1"
            ref: "core.local"
            params:
                cmd: "echo 'foo'"
            on-success: "task2"
        -
            name: "task2"
            ref: "mypack.workflow2"
            params:
                result: "{{ task1.stdout }}"  # here we pass parameter "result" to the mypack.mywfaction action which is a workflow

workflow2.meta.yaml

---
name: "workflow2"
description: "..."
runner_type: "action-chain"
entry_point: "workflow2.yaml"
enabled: true
parameters:
  result:
    type: "string"
    description: "Result from a previous workflow"
    required: True

workflow2.yaml

---
    chain:
        -
            name: "task1"
            ref: "core.local"
            params:
                cmd: "echo {{result}}"  # Here we echo the variable "result" which was passed to the workflow as a parameter