Inspired by this thread :
https://forum.xda-developers.com/galaxy-s9/help/galaxy-wearable-app-rooted-phone-help-t3838503
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If it's not already done, install the "MagiskHide Props Config" module from Magisk and then reboot.
Open a terminal emulator and run "su" then "props", when the module is loaded, type "1" to edit fingerprint, "f" to pick a certified fingerprint, choose "Samsung " (or that of your phone), then "Samsung S7 Edge" (or that of your phone). For all of the manipulations when the module asks you to reboot, don't reboot.
After that, go back to the main menu and choose "Improved hiding" and enable it.
Then, go back to the main menu again and choose "Add/Edit custom props". Now we need to change everything that is related to Samsung.
Do theses steps for every prop we need to edit :
1. Type "n" to add a custom prop
2. Now we need to say which prop we need to edit : "ro.config.tima"
3. If the value already exists it will show you what is the actual value of the prop : "1", and if it doesn't exist, double check that you didn't make any mistake when typing it and if not, skip it.
4. Then type : "0"
5. The module will asks you for when do you want this to be applied ? Just keep "default" and validate with "y"
6. Now you can reboot your phone, delete all the data of the Galaxy Health app and it should open !
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Work OK whith my Samsung S7 Edge whith root stock rom