Is it planned to implement an IdentifyGraphicsOverlayAsync() method that accepts a rectangle as input geometry for intersecting? In the previous major release, the HitTestAsync() method accepts both a point and a rectangle.
Typically you'd use a spatial query against the FeatureTable to accomplish this.
The hittest method you're referring to isn't available in the 100.x generation, because it relies on a different (but much faster) rendering engine (it was really just exposing a WPF hittest feature, but we don't use WPF to render the map any longer as it was just way too slow for complex maps).
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