I have done this effect many times without third-party plugins using CC Page Turn. Combine it with some some camera animations or transforms and blurs, and you can sell the 2D animation as 3D pretty convincingly.
Depending on your version of Ae, you may have Freeform bundled. This is a great effect for bending layers. If not, you can get it from Mettle.
If you buy the template linked in the video, you could see how the author did it.
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