Hi,
The Quartus Prime software helps to plan migration of the design to a different density device in the same family. You should indicate that to the software early in your design by selecting devices that are available for migration (Assignments -> Device -> Migration Devices). The tool then allocates pins to the design which are common in the migratable device.
More resources below:
https://www.intel.com/content/www/us/en/docs/programmable/683475/19-4/device-migration-planning.html
https://www.intel.com/content/www/us/en/docs/programmable/683143/22-1/migrating-assignments-to-another-target.html
Regards
Occasional Contributor
