What are the issues involved in doing this? Will there be any fees involved? Will this be a taxable event?
Robinhood stopped supporting transferring stocks from another brokerage to theirs early this year. (Because they transitioned to their own clearing house) and they don’t have the capability (yet) to do this. You will have to sell the stocks and transfer the money into RB for now.
Some of the espp stocks and IPO stocks cannot be transferred for upto 1 year. You can sell them but can't transfer. Mostly due to tax calculation and accounting reason.
Of course it’s your money. You will pay tax on the gains