It only records the last execution of ora_cleansp.
The information is logged in the event_log file.
The information is displayed in the event_log file as follows:
"ora_cleansp was carried out on Thurs April 26 09:59:10 EST 2019 by user for SID"
The information is accessible as long as the event_log file has not been removed or truncated during housekeeping.
You can take a copy of the event_log file prior to executing an ora_cleansp and retain it outside of the SharePlex environment.
Other than this, there is no mechanism within SharePlex to log the history of ora_cleansp executions during the life of the current SharePlex instance.
As to what comprises a SharePlex instance, please refer to article 53464.