Re: how to transfer Ledger BTC to a new ledger wallet (anonymously)
Perhaps I was not clear. The goal is to get the coins from point A to Point B without a trace. Do I have to spell it out any more clearly?? Lol.
If your friend's goal is privacy (from an ex or something along those lines,) she can merely send the funds to an exchange that allows HD addresses, like Coinbase. Then she can reset her Ledger with a new seed (optional) and send the funds back. They'll be nearly impossible to trace without a warrant.
If she needs more privacy than that, then a mixer might be a good choice. See this post by theymos that has some excellent advice:
https://bitcointalk.org/index.php?topic=5146241.0