You can use Hotjar without asking users for consent (with a cookie notice / banner) if you do not collect personally identifiable information.
To stop Hotjar from collecting them:
Step 1. Click user icon in the top right corner of the screen and choose “Orginization settings”
Step 2. In the “Data suppression” pane, mark the first 2 options.
Step 3. In your Hotjar integration choose “Load without waiting for consent”
Step 4. (Optional) Sign a DPA if it is required in your country.
Here you can read the DPA and find more information about the process.