HRV on Fenix6

Hello,

I've been using a Fenix3 and HRM-Run for years and enabled HRV by following this guide: https://sporttracks.mobi/blog/tracking-hrv-garmin-watches. How do I enable HRV on a Fenix6? I use runalyze.com to analyze the HRV readings but obviously it's not in the FIT-file by default.

Best regards,
Tobias