When exporting to AAF with the Enforce Avid Compatibility option on, Pro Tools generates Media Composer-style clip gain data, based on the clip gain data on each track.
The clip gain of Pro Tools clips with static volume between -inf dB and +12 dB will translate directly to clip-based gain upon export. Dynamic clip gain and values above 12 dB will be rendered for each clip in the resulting media, to optimize compatibility with Avid video editing applications.
Pro Tools does export volume automation to OMF, but only if the
Enforce Avid Compatibility option is disabled.