I did sideload them (BP and ECG) and yes, they work fine. However, it doesn't sync, meaning I could lose all my previous measurements when the official update gets released. The spO2, I don't have to worry about considering that got pushed with their latest update
we have Galaxy Note 9 phones and Watch2. had same problem UNTIL I UNPAIRED watch, did a reset on the watch, and THEN was able to download and install the software with ECG updates! pain in the back, but worked on both phones. now have the ECG, fall detection, and latest. not sure why would not update automatically.