ADC with integrated oversampling
Yes, there are. You'll find these at the large ADC manufacturer's websites when you look for &quot;oversampling&quot;. Typically, you'll want to do that if the oversampling ADC rate would be prohibitely large, making it unfeasible/expensive to do the decimation in software or an FPGA.
Also, the SAR ADC architecture has similar effects &quot;built into&quot; their working principles.