Generally speaking, CORS policies are based on web standards and should be identical across browsers. As a consequence, Edge behavior can be expected to match Chrome's.
If you are seeing an incorrect message, please provide repro steps and we will investigate.
The Out-of-Blink-CORS flag should have no visible impact on anything. What it does is move CORS checks out of the (potentially compromised Renderer process) to a more trustworthy process, thus providing higher protection against cross-origin data theft.
There exists a command line switch which disables web security (including CORS) but I'd advise against using it, as it is unsafe and it will hide bugs.