Quadlock has been solid across two or three phones for me, if you can live with the mount on the phone itself (alternatively have another case for the phone with the mount permanently on that)
Quadlock. Dunno if they have an S10e specific case, but I use a Ringke case and the Quadlock universal mount. Not had any problems with it or any of the previous phones I've used it with.
Best bike phone mount for a Galaxy S10e?
All the 'best phone mount' guides I can find online seem to be iPhone only or ancient.