Hello, could you tell me, where is the best point for frame rate conversion in chain from european 50Hz HDMI camera (Canon Legria HF R66) to Youtube stream 30p ?

1. Set 30p input channel of vMix (HDMI to USB3.0 capture device) for camera with 50Hz HDMI output and vMix preset have in 30p
2. Set 25p input and 30p vMix preset
3. Set 25p input and 25p vMix preset and 30p RTMP encoder.
4. Set 25p input and 25p vMix preset and 25p RTMP encoder and let to convert by Youtube server.

I know that all options work (better or worse). I would like to know what is the smoothest (best quality) conversion.

Thanks.