This is a super secret workaround.
You’ve done this: set transform keyframes to change the position and scale of an object. You set the interpolation to linear, yet the thing still eases in and out. You play with the bezier handles but no joy. There is hope, because there’s a simple workaround that will allow you to make your animations nice and direct with no easing.
It’s all about adding a keyframe to the frame next to your current keyframe, then deleting it. It’s quite simple really, and it works.