Which Adobe Products have offline activation?

CS5+6 may still be activated online, but since they are not supported now I do NOT know if telephone activation still works

Which CS products & versions do you have?

CS1, CS2, CS3 and CS4 activation servers are dead & gone.

CS5 and CS6 are on life support. But they can still be activated providing you have the following:
1. your original media (disks or downloads) that you received at purchase and a way to read them,
2. a legitimate serial number for that version, language and platform (Win/Mac) and if it was an upgrade, a qualifying serial number from an older product,
3. an older operating system that can support legacy 32-bit apps.

4. Offline Activation details below:

https://exception.licenses.adobe.com/aoes/aoes/v1/t1?locale=en

NOTE 1 : Creative Suite installers won't work on macOS Sierra, High Sierra or Mojave without terminal workarounds. See the help article below.
https://helpx.adobe.com/creative-cloud/kb/install-creative-suite-mac-os-sierra.html

NOTE 2: Legacy Creative Suite will never run on Catalina, Big Sur or Monterey. Nor with they be tested with Win 11.  Only the latest Creative Cloud products are compatible with new operating systems.

NOTE 3: Legacy Creative Suite is discontinued & unsupported. So Adobe can't help you except to reset your activation count.

Hope that answers all your questions.

there is no adobe product that can easily be activated offline, and i know of no list of what can be activated offline given the right set of circumstances.

ie, some people have been able to activate some older adobe programs offline, and it may be possible for enterprise subscribers to activate current programs offline.