The Sumerian word en could be translated as "lord" in English, but "lord" doesn't mean "god." A landlord isn't a "land-god", nor are the "lords and ladies" equivalent to "gods and goddesses." In English, when addressing the Judaeo-Christian god, "lord" is a title. Similarly, you could call a knight "sir" but that wouldn't make "sir" mean "knight."
The Sumerian equivalent to 'el (the common noun, not the name of the deity) would be dingir. The Akkadian cognate of 'el, by the way, is ilum. Looks a lot less like en, doesn't it? In fact, in cuneiform, Akkadian ilum and Sumerian dingir use the same sign (see the above link for what that looks like).
However, with en, the Sumerian uses different signs, and is equivalent to the Akkadian bēlum instead, which in turn is cognate with the Hebrew ba'al.