There is not really any right or left wing in Frankfurt. Eintracht Frankfurt is a complete melting pot of cultures and ethnicities just like the city itself.
Our support actually is often the target of right wing abuse as we most likely have the weirdest mix of everything on our standing terrace. Germans next to Croats, Serbs, Turks, Arabs etc. If you ever been to Frankfurt (the city) you might have noticed that the amount of "foreigners" is pretty big and I don't mean that in a negative way. It's just a melting pot...
When I grew up Frankfurt had a massive issue with a Nazi following especially in the early 90s. However that was generally an issue with almost all bigger football clubs back when the wall came down. But looking back I can only wonder why some of the songs that could be heard on a regular basis were tolerated. Especially coming from fans supporting a club that was known as the "Jewish boys". But Germany at the beginning of the 90s was a complete shit show of a society anyway.
I would consider the old Hooligans that were around in the early 90s(and are around still) to be more right wing.
The rest puts politics aside and just supports Eintracht. There are some groups of Ultras Frankfurt that are more left (Droogs for example), but overall I wouldn't consider our support to be right or left.
Hansa Rostock is definitely right, St. Pauli left but it's a mix of everything on our end.
If you are refering to the clashes in Italy there was no political motivation behind them and it was not one specific group. Just a mix of Ultras and Hooligans.