Yes. HubSpot runs in a browser and lists Chrome, Firefox and Edge as supported, all of which are available on Linux. There is no desktop program to replace.
HubSpot by HubSpot, Inc. · Business & accounting · Works in a browser
HubSpot is a website. Its own help page says a supported web browser on a computer is needed for
full functionality, and lists the latest versions of Google Chrome, Mozilla Firefox and Microsoft
Edge on Windows. Those three all have real Linux builds, so the product you sign into on Linux is
the same product.
Nothing needs converting. Contacts, deals, emails and reports live on HubSpot's servers, so
switching machines means signing in again.
One practical warning from HubSpot's own documentation. Calling from inside HubSpot depends on the
browser supporting WebRTC properly, and HubSpot points at Chrome and Chromium-based Edge for that.
If you make calls through HubSpot, install Chrome on Linux rather than relying on Firefox, and test
a call with your microphone before you need it for real.
The pieces to check separately are the add-ons. The HubSpot Sales extensions for Outlook and for
Office are Windows software and do not come across. The browser extension for Chrome does, and the
Gmail integration works because Gmail is itself a website.
Only worth looking at if you want to leave HubSpot. Browser-based CRM with a free single-app plan, simpler and much cheaper, with far less marketing automation.
Your files: Nothing proprietary to convert. Contacts and deals move as CSV exports.