I do not know what a Sprout 2 projection is... Can you elaborate?
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Sprout 2 is a very lightweight and performant means of capturing a source in OBS that both utilizes GPU resources and more importantly can hide things like UI in the actual projection, making it easy to make on-the-fly changes without having to show viewers. The creator of VSeeFace, which uses it, explains it pretty well here: https://www.vseeface.icu/spout