You'll need Broker Endpoints on both servers, because Broker conversations are two-way (send-ack). You also need the following four routes:

1. On Initiator database: Route to target Service and...

(pasting a reply from a similar question from last year)

The behavior changed in SQL 2016:
https://support.microsoft.com/en-us/help/4010261/sql-server-and-azure-sql-database-improvements-in-handling-some-data-t

If you run queries on a SQL 2017 database set...

When planning for recovery, I favor 'lower tech' solutions - keep things as simple as you can while still hitting your RPO/RTO. I deal with log shipping on 100TB++ databases...

It seems weird that the offline upgrade occurred on all three nodes. Once the database is upgraded, it's upgraded. The changes made to the database during the upgrade propagate to...

If you're running Windows Pro 8.1 or later, Hyper-V is built in. Just hit the Windows key, type "Hyper-V" and then select the option to add Windows components. Select Hyper-V...

For our upgrades from SQL2008r2 to SQL2016, we used Microsoft's SQL Server Database Experimentation Assistant:
https://blogs.msdn.microsoft.com/datamigration/2017/07/25/dea-2-1-general-availability-release-overview-database-experimentation-assistant/

This tool does exactly what you're after, using your actual workload.

That's a license...