Hi,
Old, non Chromium-based Edge might be supported by TC 12, but I am not sure and this needs to be checked.
As per my understanding, modern Chromium-based Edge requires latest TC versions in order to be supported. Like for Chrome support itself.
Generally speaking, web tests in TestComplete are cross-browser. (Unless test code uses browser-specific object properties like contentText and textContent instead of cross-browser wrappers (contentText) provided by TestComplete.)
But the devil is in details and the real level of cross-browser support for your tests depends on both, the tested web page and your test code. If web page renders differently in different browsers (say, because of scripting specifics), you might will need to adjust your script code. Likewise, if your test code interacts with windows like File Save, test code also might require adjustments for different browsers.
So, as basically suggested by Marsha, I would install trial of latest TC and check how well existing test code for IE works with Edge.
