Freshsales is another popular CRM and you may need to update existing Freshsales data when customers are migrating to Dynamics CRM or using both CRMs.
You can integrate MS CRM and Freshsales CRM easily using Microsoft Flow and Freshsales REST API.
Following image is a sample of lead creation in Freshsales when a lead is created in Dynamics CRM.
You can create a flow to send a HTTP request to Freshsales API from Microsoft Flow.
With this approach, you may able to refresh your Freshsales data from Dynamics CRM using Microsoft Flow with less effort.