Great writeup @inginero , this is exactly what is happening with me. I can sync my weight from Wyze Scale to Google Fit just fine, however Google Fit is not syncing weight or additional weight metrics over to MyFitnessPal, which then prevents MyFitnessPal from syncing weight metrics over to Garmin Connect.
I would love to cut out some of these “middle” apps and have Wyze directly connect with Garmin, however, I understand that Garmin is like Apple, and likes everyone to use their “proprietary” products; I am not willing to spend $150 on a smart scale that does the same as my Wyze Scale.
If Wyze could connect directly to MyFitnessPal, I believe that potentially could solve the problem…
I will also be reaching out to Google, to see if they can get a connection built directly to Garmin (to cut out MyFitnessPal) and I will also see if Garmin will get a connection built to integrate with Google.
However, since these relationships are out of our hands, I will also request Google and MyFitnessPal respectively to sync weight metrics back and forth, as of right now Google is only pulling weight from MyFitnessPal, and not sending weight metrics to MyFitnessPal (https://support.myfitnesspal.com/hc/en-us/articles/360032273832-Google-Fit-FAQ-and-Troubleshooting).