When doing shnayim mikra, do you pronounce Hashem’s Name when reading the Targum?
Yes we do, the same way we say Hashem’s name when reading the posuk twice. We are allowed to say Hashem name whenever we are learning davening or saying praises of Hashem. Especially while saying shnayim mikra, that we should be saying the posuk correctly.
Taz O:CH 621-2, M:B 215-14, Igros Moshe O:CH 2-56.