What data do you have?
Are you interested in where they are from? or just the aggregate?
Do you need to do this in arcgis online?
https://usflibrary.maps.arcgis.com/home/webmap/viewer.html?webmap=b310b0eeb42c42c5a38ec8f6444c5e80# this is the map I am working on. I was looking for just the aggregate but knowing who exactly would also be a nice thing to have if you don't mind helping with that also.
You may find some inspiration in the United States Census Bureau's tools and datasets aimed to address migration within the United States.
Here is an article from Census that discusses the tools: https://www.census.gov/library/stories/2019/04/moves-from-south-west-dominate-recent-migration-flows....
Geographic Mobility: 2017 to 2018: https://www.census.gov/data/tables/2018/demo/geographic-mobility/cps-2018.html
CPS Historical Migration/Geography Mobility tables: https://www.census.gov/data/tables/time-series/demo/geographic-mobility/historic.html
American Community Survey State-by-State Migration tables: https://www.census.gov/data/tables/time-series/demo/geographic-mobility/state-to-state-migration.htm...
American Community Survey County-by-County Migration Flows: https://www.census.gov/data/tables/2016/demo/geographic-mobility/county-to-county-migration-2012-201...
Census Flows Mapper: https://flowsmapper.geo.census.gov/map.html#
Flows Mapper REST services: https://gis.geo.census.gov/arcgis/rest/services/FlowsMapper