Designing a Platform to Serve Multi-Tenancy with Processing data from Batch, REST and Queues

I m trying to design a Platform which can have multiple Publishers and Consumers. It can expose the Layer on REST API as well as GRAPHQL. Now if we want to have an Orchestration or Workflow layer which supports following things

1. SAGA base Message Processing.
2. REST API based Step by Step execution
3. REST API based Orchestration

with keeping all the Microservices decoupled and Transformation; Routing done through the Workflow/Orchestrator itself. Any Tool or Framework in market can help such as NETFLIX Conductor. Need Suggestions on this how can move forward.

At the end it needs to

1. Easy to Configure -- while adding new API; New services.
2. Support Observailibility
3. Plug and Play configuration
4. Things such as Service discovery and Cloud Agnostic if required