Wealthfront offers the ability to blacklist stocks in your account (the feature is meant for people legally prohibited from investing in certain tickers).

It won’t exclude from regular indexes, but it will exclude from the direct indexing. I’ve been using it to exclude NVDA ever since it peaked (or at least reached the peak valuation I’m comfortable with)

Wealthfront’s portfolio minimum used to be $100k, but I think they have a new direct indexing product with a $5k minimum.