What robo advisors can do.. is sell say.. asset A that perfectly tracks an asset (say S&P 500)... and then buy asset B that perfectly tracks an asset (say S&P 500).
So you end up with the "same thing" at the end of the day, but got to harvest some losses.
That said, I think there are some iffy legal situations here, and you run the risk of breaking the law here.
TLH is real, but "sell yourself the same asset at a loss" sounds fishy to me.
Because with TLH its not "the same asset" in that its not
(a) the literal same item moved from one hand to the other.
(b) its not the same item ticker (basically a day trade across accounts)
(c) Its not buying/selling with yourself
If you sell yourself the security, it never left your hand so you didn’t realize a loss.