I'm preparing a matte paint in PS which i need to use a stock of fire footage inside. I took a single frame of the fire, then duplicated it dozens of times and in various sizes and placed in differently on the matte paint.
Now the question is; is there any possible way to import those layers to after effects as a position and size information for replacing still layers with actual fire footage?
No. This is not even an AE issue. Photoshop simply doesn't create persistent transform data, it's only evaluated at runtime based on the layer bounding box. the only exception from that rule would be smart objects or PS animation, but unfortunately AE doesn't care for that and will only import the rasterized result or refuse to load the file at all.