Bug Report: Premiere / After effects keyframe interpolation
This issue has existed since at least the 2020 versions and still in 2021. When animating Motion properties like scale and position in Premiere Pro and then bringing the sequence into After Effects via Dynamic Link or via import, keyframe interpolation does not always match. For example, if Ease In or Ease Out are set for Scale keyframes in Premiere, these keyframes show up in After Effects as bezier keyframes with 0.01 influence, and are effectively linearly interpolated. Position keyframes set with Ease In / Ease Out / Bezier interpolation in Premiere come into After Effects with correct interpolation sometimes but not others. Auto Bezier keyframes on either property export to After Effects with different interpolation most of the time. In the particular case of exactly two scale keyframes with Ease In / Ease Out interpolation in Premiere, manually setting the influence to 33% (not 33.333%) in After Effects seems to make the animation match between the two programs. But this workaround is not a solution with more complicated keyframe setups.
Carlos Ziade commented
even though we now have mogrts, but video editors still feel the need to take their premiere pro animations further through after effects much more advanced tools, so preserving keyframe interpolation between the 2 programs is highly recommended. Even having After Effects, Premiere Pro, Audition, and Media Encoder ship together as 1 app looks more practical, just like Resolve. Most creative agencies are no more recruiting a pure editor, they always state that they want a motion designer with editing and sound skills.