The .apk file is 42MB, and when that gets uncompressed it's an additional 100MB. Plus the temporary space needed to do that, so you need at least 242MB of free internal storage just to download and install it. But it needs about 2GB of free storage after it's installed.
Assuming that you're trying to install it using Play on the phone (not the web browser, or a web browser on something else), You need 2GB of RAM so an S7E should do it, if you have close to 3GB free internal storage before trying to install it. If you meet all the requirements, the only thing I can think of, aside from a hardware failure in the phone is that, for some reason there are multiple versions in the Play store, and you're being sent the wrong one (which I don't believe is true - Unreal Engine should be the same for all android phones).
The only other possibilities are something in your internet path (your router overheating, your ISP [if you're on WiFi or your carrier if you're on mobile data] not allowing large downloads, etc.)