Ultracopier

Ultracopier is file copying application software for Windows, macOS, and Linux. It is based on and supersedes SuperCopier. SuperCopier and Ultracopier differ mainly in terms of appearance. SuperCopier essentially serves as a skin for Ultracopier, with slightly higher CPU usage. SuperCopier typically refers to SuperCopier 3 and earlier versions, while Ultracopier refers to SuperCopier 4 and later versions, now known as Ultracopier 1.4.
Features include:

Pause/resume transfers
Dynamic speed limitation
On-error resume
Error/collision management
Data security
Intelligent reorganization of transfer to optimize performance
Plugins

Normal vs. Ultimate version:

The source code is identical, and it falls under the same license.
The ultimate version includes alternate plugins.
Both versions are without DRM and can be redistributed freely.