The Syslog-ng Windows Agent is not included with Syslog-ng PE 7.
There is support of Syslog-ng Premium Edition 6.0.x Agent for Windows until July 31st 2020.
Additionally One Identity is committed to offer a suitable agent for collecting application logs on Windows platforms in the long run. We will make sure that an advisory notification about what this solution is will be sent out well before this end of extended support date.
Please see the following notification for further details: