I am recovering right now from a felting mishap (top load, though) but I have indeed felted successfully in a front load HE washer, hot wash, cold rinse. One thing I remember, though, is that this particular model had a high water setting on it, which the manual actually said was for people who felt they needed to SEE the water to feel like their clothes were getting washed, but it did raise the water line significantly, not sure if yours has that, you might want to check the manual for a setting.
Another thing you can try, since items usually felt better with agitation, is to try to “trick” the machine by throwing a few pairs of old jeans/towels in, which will get you more water and also provide some friction.
It would also depend on your yarn, there are some yarns that will actually felt just from moving around the back seat of my car with the Florida heat and humidity (Malabrigo,) so if you’re working with something like that, you should have pretty good success. The big downfall for me was that it was incredibly difficult to monitor progress without wasting a ton of water having to drain each time. Oh and one more thing I learned, use a TEENY amount of soap for felting in an HE, the knitted item will retain it for subsequent washes.
Your best bet might be to make a small swatch and throw it in the wash so you can have a better idea before felting your actual item.
