I’m not an expert at Theosophy, but I have a general understanding.
Somewhere I read she claims that because black people are the original root-race, they developed here longer without influence from alien culture. It is the whites, asians and hispanics who received upgrades by aliens from another World.
I see no other indictation to call her a racist.
Is there something about Blavatsky I must have missed?
She is the founder of Theosophy, a reinterpretation of Tibetan Culture.