List out all the possible ways to migrate Quicksight dashboard from one account to another account
There are 2 ways to do it:
Via a template that comes with in-built version control
Porting Content :: QuickSight DevOps
Using the recently added APIs for describe/create analysis/dataset/dashboards.
New Amazon QuickSight API Capabilities to Accelerate Your BI Transformation | AWS News Blog
I hope it helps,