Is it possible to manage swap using Plesk?
Plesk does not manage swap space. Refer to the corresponding operating system manual for exact instructions on managing swap space/partition.
Note: according to Plesk hardware requirements, a minimum of 1 GB swap is required for Plesk on Linux server. Moreover, generally, it is not recommended to disable swap completely - https://www.redhat.com/en/blog/do-we-really-need-swap-modern-systems
The RAM usage may increase due to the high number of visitors or during daily maintenance tasks (e.g. statistics calculation, spam train, etc.). With swap disabled, the lack of RAM may lead to a server crash.