Regarding the support of TDE ( Transparent Data Encryption ), Imperva agents are not affected by this feature.
TDE applies to only data at rest, which means data which is stored in the HDD's. The data is already decrypted when received by the Imperva Agents.
There is no need for any specific advanced agent configuration as TDE applies to only data at rest - when the database query is executed the data is decrypted as soon as it leaves the disks where its stored before being intercepted by the Imperva agent.
I hope this helps.