Sefaria is a popular and novel Web site with various translations of holy texts; are any rabbinic authorities on record as endorsing or forbidding it? Translations can be subjective, it is inevitable that one's view of Judaism will shine forth.
Emeritus Chief Rabbi Jonathan H. Sacks, "In Praise of Sefaria":
"Sefaria is one of my favorite things in the entire contemporary Jewish world. It is taking cutting-edge technology and doing something very spiritual by it. What it is doing is opening up the rich treasury of our texts - we the people of the book, the people that never stopped writing and commenting on books - and it's opening that up to all Jews and indeed everyone, everywhere. And secondly, it is allowing that extended conversation to be trackable, the way one text begets another text, and all the voices of our history are in conversation, trying to decode what G-d is trying to tell us about how we ought to live. Sefaria in general is just brilliant. ... The Talmud belongs to all of us, it is our shared heritage, and because of Sefaria it is now really accessible anywhere by anyone so you've done something really, really important here, you fulfill the mitzvah of Talmud Torah and make the Sefer Torah, the ספרייה of our people and our soul, available through this great technology, across the world. Well done, I hope a lot of people use it."
Will modern commentaries be included in Sefaria?
Yes, although they may be presented differently than traditional, canonical commentaries. We want to offer access to as many points of view as possible, but we don’t want to impose points of view on anyone. Our first focus is in making the core texts of our tradition available. When we get to including modern and contemporary texts we may only display them once a reader has expressly asked to see them.
“There are no heresies on Sefaria,” he said. The more democratic nature of Sefaria allows the inclusion of viewpoints that might not make it into more religiously observant settings, he added.
IsraelReader: Given the above, I wouldn't expect any mainstream Hareidi rabbinic authorities to go on record as endorsing Sefaria.