It is most likely Blink under the hood[1], but the user agent doesn't give you any information on that subject.

This is Edge's user agent:

    Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/42.0.2311.135 Safari/537.36 Edge/12

It's almost the same except the MMS/number being replaced by Edge/number, and Edge is using a totally different engine than Chrome.

[1] business-wise I don't see any good reason to revive a engine dead for 4 years (Presto) or even worst, develop a brand new one.