Mono downmix

I’d like to to mix down to mono from stereo with both channels 50% of volume. For now, I’ve been using Sound Forge’s batch process to do that because mono downmix seems to get distorted in Nuendo. How do I achieve the same results directly when exporting audio from Nuendo?

Thanks,

Turn the master down according your pan law (by default 3dB)

Simple as that! Big thanks!