After more investigation, I see that the same waypoint loses some commands when its reimported and then exported again.
Mission made in Metashape and exported out as XML in referenced CS:
<Placemark>
<name>Waypoint18</name>
<visibility>1</visibility>
<description>Waypoint</description>
<styleUrl>#waypointStyle</styleUrl>
<ExtendedData xmlns:mis="
www.dji.com">
<mis:useWaylineAltitude>false</mis:useWaylineAltitude>
<mis:turnMode>Auto</mis:turnMode>
<mis:heading>0</mis:heading>
<mis:gimbalPitch>-37</mis:gimbalPitch>
<mis:actions>ShootPhoto</mis:actions>
<mis:actions param="22">AircraftYaw</mis:actions>
<mis:actions param="-90">GimbalPitch</mis:actions> <mis:actions>ShootPhoto</mis:actions>
</ExtendedData>
<Point>
<altitudeMode>relativeToGround</altitudeMode>
<coordinates>-118.50362178450798,34.173828195393639,7.8964029783034846</coordinates>
</Point>
</Placemark>
Same mission plan exported as path and reimported to duplicate mission plan:
<Placemark>
<name>Waypoint18</name>
<visibility>1</visibility>
<description>Waypoint</description>
<styleUrl>#waypointStyle</styleUrl>
<ExtendedData xmlns:mis="
www.dji.com">
<mis:useWaylineAltitude>false</mis:useWaylineAltitude>
<mis:turnMode>Auto</mis:turnMode>
<mis:heading>-177</mis:heading>
<mis:gimbalPitch>-48</mis:gimbalPitch>
<mis:actions>ShootPhoto</mis:actions>
</ExtendedData>
<Point>
<altitudeMode>relativeToGround</altitudeMode>
<coordinates>-118.50358779586475,34.173876824511773,8.2329423697085531</coordinates>
</Point>
</Placemark>
The ReImported file lose the AircraftYaw and GimbalPitch param.