Hey, thanks for your message!
You can find the best stock brokers in Germany here: https://brokerchooser.com/best-brokers/best-stock-brokers-in-germany
If you’re interested in futures and penny stocks along stocks and ETFs, Interactive Brokers can be a solid option. MEXEM and Saxo are also quite good — they offer stocks, ETFs, futures, and penny stocks as well.
Regarding Charles Schwab, thanks for flagging this — we’ll review and correct the information about availability in Germany.
Best,
Andris