Circle Crop Premiere pro beta 25.2

You should be able to achieve a circle crop/mask with new Film Impact addition of Rounded Crop. Keyframing the offset allows you to move the mask where you want it

You can use a Track Matte Key on the video track, selecting the graphic. Or you can drop the video into the graphic and place it under the circle. The graphics layers can include pictures and video.

Oh, and here's the thread regards the Obsolte effects:

https://community.adobe.com/t5/premiere-pro-beta-discussions/now-released-obsolete-effects-transitions-and-presets-removed/m-p/14703879

At the bottom of the Properties Panel

The Circle effect from the Obsolete folder after many years has been removed (all in the obsolete folder). You can make a circle in the properties panel with the graphics and use that as a mask or a circle.