Is there a way to actually do Open With on multiple files?
You could just select Open and all would do what you ask as well. . .
From the Control Panel, go to Default Programs, select Associate a file type or protocol with a program, and then change the default for both .jpg and .jpeg to Google Chrome.
Now when you select all applicable JPG files and select Open, all the selected JPG files will open with Google Chrome. This method uses the multiple-selected JPG file right-click Open option rather than Open With option so that may suffice for the need as you describe.
