Image cut out and optimisation for Shopify

I have about 70 images that have been professionally shot and i need them rotated, optimised for shopify (max 20mega pixels) and with backgrounds removed or all backgrounds with the same grey.

Plus as an extra please supply an additional cost for adding a false dropshadow to bottom right on every image.

I need to be able to drop and drag to shopify pages - so also help with shopify would be useful