You can use a canvas and image manipulator to do most of that automatically.
Resize the sprite to whatever you want in the layout editor or at runtime and put a canvas over the sprite. Have an event:
for 1 to 150 (number of frames)
- Sprite: set animation frame to loopindex
- canvas: clear to transparent
- paste sprite to canvas
- send canvas's image to image manipulator using copy from Sprite (works with canvases)
- save as PNG "animation" & loopindex & ".png"
That will save all of the frames to PNGs automatically. Reimport to construct using the import frames feature so you can import them all at once, then open the animation to edit it, alt-click with the hotspot tool to set the hotspot for all the animation frames at once and alt-click crop to crop all the frames at once. Much faster.
While trying to get it right, you might even be able to load all the frames from disk at runtime as well, by for 1 to 150, setting the animation frame of the sprite then loading animation frame from file "animation" & loopindex & ".png", though construct sometimes crashes when using this feature. Also, you need to make sure that a sprite has the number of frames you'd need before trying this at runtime, because you can't create animation frames at runtime.