A: Does Re:plain offer any way to track agent productivity? Can I get reports by operator of the calls performed? Can these reports be customized by site?
——You can use Conversation rating add-on to see ratings of your operators.

Re:Plain offers any form of evaluation of customer service? At the end of each service, is it possible for the customer to make an assessment with criticism or suggestions?
——Yes: https://replain.cc/store/conversation-ratings

Does Re:plain have any integration with CRMs? Is it possible to do this integration? Is there any content about this?
——Yes: https://replain.cc/store/replain-api

Is it possible for the operator to see that there is a visitor on the site and actively contact him or does it just act as a button that the visitor can or cannot click?
——No. It just act as a button that the visitor can or cannot click

Is it possible for a second operator to be called into the conversation?
——You can transfer client between operators and see conversation history

Is it possible to create a second level of administrator, which is limited to specific sites and can only include and exclude operators on those specific sites and monitor and manage the conversations/calls of these operators?
——Not yet.