Have you tried a very different spelling when checking indexes, etc. for "Ewe'? The names "Yoe" or "Yoh" would sound about the same when spoken, and a census taker or other person might have used one of those spellings - -,
One of my g-g-g-grandmother's surname was shown as "Ewe" in the 1790's marriage record in Frederick Co VA. I found no other records of a "Ewe" in that area, but did find other persons named "Eoh", "Yoh" and "Yoe" '- - .(Still haven't determined her exact family, parents, etc.)
Good luck with your search.