This is most likely a display/calibration issue, not an export-setting problem. Your JPEG can look correct on the monitor you edited on, yet appear flatter or more blown out on another screen if that screen has different brightness, contrast, color gamut, or poor viewing angles.

A few key points:

• Laptop screens are often less accurate and more sensitive to viewing angle.
• If the image looks right after export on your editing computer, Lightroom/export settings are probably not the main issue.
• Without calibration, two monitors rarely match well.

What you can do without hardware calibration:

• Put both screens side by side and manually adjust the laptop’s brightness/contrast/color to get closer.
• Start from neutral display settings if possible.
• Use monitor calibration/test images and guides to manually tune brightness and contrast.
• Check your editing environment: strong room light or reflections can affect judgment.
• Avoid editing with the screen set excessively bright.

A hardware calibrator is the best solution, but manual adjustment can still improve consistency a lot. Just keep in mind that different displays will never look exactly the same.