There is no fixed cap. The connector does not impose a per-account or per-user limit on the number of data sources. Create as many as your reporting needs require.
A practical note: every data source is a separate OData endpoint with its own selection of objects and filters, so a smaller number of well-shaped data sources is usually easier to maintain than a sprawl of narrow ones. Refresh performance is bounded by HubSpot’s API rate limits rather than by anything in the connector — see Why are HubSpot API limits showing up in my refresh errors?
