Knowledge base
The ability to drag and drop across apps has opened up many possibilities and one of them is a hack that lets you grab a load of image search results and pop them straight into Photos. It requires a bit of finger athleticism as you have to hold down on the images while performing other tasks but it certainly speeds up the process of bulk saving.
Keep dragging and dropping
Just be aware that the images are unlikely to be of the highest resolution but it’s a good way of, say, building up a reference portfolio of interior designs or figuring out what images may be suitable for a project. As a bonus you can even highlight text contained in any image listed in a set of search results and copy, look up or share those elements too.