Same Problem here in UE 5.2
The SetPosition from the Target User Widget does not have any effect.
Using the setTransform of a canvas wrapper instead ran me in to some scaling issues when tried using ProjectWorldLocationToWidgetPosition to set a Point of Interesst Widget (WorldMarker).
The coordinates are correct when having the game on fullscreen but when the game runs in windowed mode with custom resolution the coordinates have an offset due to the viewport scale.
Hope this will get fixed…