Make sure that both Premiere Pro and After Effects are on GPU Acceleration renderer,
and both are using the same Color Space. These can be checked in Project Settings.
Let us know what happens.
Concerning Motion Blur, you can animate your text inside After Effects and turn Motion Blur on,
from both the text layer and composition, as well as setting the Shutter Angle to 360 or whatever,
from Comp Settings. If animating text inside Premiere Pro, set Composition Shutter Angle to 360
or whatever, from Transform effect, but keyframing should be done in Premiere Pro, using Transform
properties for the motion blur to have effect.
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