How to make automatic backup of files when connecting a portable HDD?

Question

Data archiving

Windows 10
I make backup copies in Acronis True Image to a hard drive.
But you also need to copy these files to a portable hard drive, which I connect from time to time.
Acronis has a backup duplication feature, but it works when a backup is created and a portable HDD is connected (for duplication).
My situation is different.
I need to set it up so that:
I plug in a portable HDD and if there are any changes on the PC in a certain folder, they are copied to the portable HDD.
Tell me a program that can be set to autoload to do it automatically when you connect a portable drive (I will copy the created backups * .tib)

Answer 1

A simple schedule script won't help?

Answer 2

PureSync

Answer 3

FreeFileSync - https://freefilesync.org/ has a RealTimeSync tool

Answer 4

Backup when connecting an external drive is available in Veeam Agent.