Migrate replication from SQL Server 2008 R2 to SQL Server 2016 - Old to new hardware I will be working on a project shortly that would involve moving the replicated databases off of old to the new SQL Server instance. I haven't done this in the past so I don't have much knowledge either on how to move ahead except to do some research. 

As of this date our current config sits on a Windows 2008 R2 server with SQL Server 2008 R2 and publisher along with the distributor is the same SQL Server instance e.g sqla and the subscriber is sqlb and also now sqlb is acting as a publisher and distributor for sqlc... these are all pull subscribers with one way transactional and snapshot replication. 

Now, back to my original question. Is there a way to migrate the databases off of the old to the new with least downtime so I don't have to script out and reinitialize subscriptions as it would take a lot of time (that's what most of the people mentioned on google). Do we have any hacks or tricks to make this work without causing problems or if there is any step by step to work it out even if we use script method.
I am going to that with my same type migration this past February, I had to do all systems in one day. I had all my servers prepped before had with the exact same folder structure and included the folder name MSSQLSERVER10.  I shut down all services and disabled them.  I then copied all the system databases to the exact same folder location on the new system.  I started SQL Services only to ensure systems came up.  Once that was confirmed I brought over 1 of the replicated systems to ensure they come up.  Once that was successful, I brought over everything else, turned the systems on and waited a bit to start the agent as I wanted to check and ensure every db came back online.  I then turned on agent service on Primary first and then started all of the secondaries.  Forcing replication, or rebuilding it was not an option for me.  There are other ways to do it but this was the one I decided to use for the environment we have.  I was luckily enough to have an outage window to complete this.