Lyoto Machida has a Background in Shotokan, BJJ, and even some Sumo when he was younger.
The one that you will study and practice. Karate is all based on the same basic principles from the same basic roots in Okinawa. The effectiveness is more dependent upon the practitioner then on the style.
The sport of Judo involves more hugging or grappling. The sport and practice of karate is more of a striking fighting style. Karate can be said to have the most emphasis on hand movement.
The requirements vary from school to school and style to style. In the style I practice, you have to be at least 14 to test for a full black belt. You can obtain a 'junior' black belt prior to that.
Pat Morita plays the part of an Okinawa Karate master. Much of what he taught is based on the traditional Okinawa style of Shorin Ryu karate. Yes, I teach my kids "wax on, wax off" in class! The 'crane stance' that Daniel does in the last fight is not something we teach in the style.
shotokan style
depends on the style and school, i practice Shorin-Ryu Okinawan style and Yellow is the second belt, you have to learn the first kata- Fukygata Ichi and know the basic stances.
The Wado ryu Karate style mixes the two about 70:30 to karate but I'm not sure that is what your looking for. Are you looking for a specific style or anything that combines the two?
Daniel Larusso got taught Shotokan Karate in the Karate Kid
You can pretty much find any style of karate in Germany that you are interested in, including:Shorin ryuTang Soo DoTaekwondo!
Its an Okinawan style of Karate.
You would find the listings in many of the karate histories. The book Okinawan Karate: Teachers, Styles and Secret Techniques by Mark Bishop provides hundreds of senior practitioners and their lineage.