Image cropping is a relatively simple action if you use it for GIF or PNG screenshots. After cropping it’s possible to save without image quality loss. … But as soon as JPG is involved there are actions, which can be applied without loosing image quality and other actions will lower image quality with every load → modify → save action.
Fixing the perspective distortion needs advanced algorithms and should already be applied, when an image is created, because it’s the least amount of work needed to put into the whole workflow, if it done immediately.
Creating an alpha-channel is also advanced. Most of the time the alpha channel is used to create transparency, but it can also be used for other effects like “height maps”, which is a completely different “beast”.
So what I want to say is, that even “simple task” can become complex as soon as there are minimal changes to the “standard” workflow a browser can do out of the box.
I think it should be completely avoided, since there are a lot of dedicated image apps which create good results.
I like to use https://squoosh.app/ to experiment with lower image sizes using lossy compressions like JPGs
I like to use IrfanView and its filter addOns for “simple” modifications and batch-processing of many images.
I personally would never try to implement something into TW, because it can be done much easier and much better with dedicated software.