There are many kinds of stock options, the common ones are American options, European options, Bermuda options and exotic options.
OTC equity is OTC stock, that is, the transaction is not conducted on the exchange but privately, which is not a financial derivative.
The most common equity derivatives of Goldman Sachs and Morgan Stanley are equity swap and exotic options; Equity swap is mainly aimed at executives of listed companies and major shareholders who are inconvenient to sell shares. Compared with ordinary American European options, exotic options is much more complicated than ordinary investors can understand, so it is generally conducted between financial institutions such as Goldman Sachs and Morgan Stanley.
Swap is swap. If it is a stock swap, it is an equity swap, which is a derivative of equity.
CDS is a credit default swap, a swap of bonds and a bond derivative.