* He has once voiced the same character as Yūji Ueda: Kyosuke Takakura in Nana. Ironically, in Full Metal Alchemist, they voiced bitter enemies (with Suwabe as Greed and Ueda as Kimblee). In Prince of Tennis, they belonged to the same tennis team in which Suwabe's character is the team captain; in Clamp's X anime, Suwabe's character Fuma is once again the leader of the Dragons of Earth, in which Ueda's character is a member of.
* He has also worked together with Kenichi Suzumura on several occasions:
- In Trinity Blood, with Suwabe as Mein Herr' Contra Mundi (Cain Nightroad) and Suzumura as Dietrich von Lohengrin.
- In Gundam SEED Destiny, with Suwabe as Sting Oakley and Suzumura as Shinn Asuka.
- In the drama CD version of Ouran High School Host Club, with Suwabe as Kyoya Ootori and Suzumura as Kaoru Hitachiin.
- In Clamp's X anime, they are respectively the main characters Fuma and Kamui.
- In Final Fantasy VII Advent Children with Suwabe as Tseng and Suzumura as [[Zack (Final Fantasy VII)
- In Bus Gamer with Suwabe as Nobuto Nakajyo and Suzumura as Toki Mishiba.
- In Zombie-Loan, with Suwabe as Reiichirou Shiba and Suzumura as Chika Akatsuki
- In Amatsuki, with Suwabe as Bonten and Suzumura as Ginshu
* He has also worked alongside Minagawa Junko on at least three occasions.
- In The Prince of Tennis, with Minagawa as Echizen Ryoma and Suwabe as Atobe Keigo
- In Trinity Blood, with Minagawa as Ion Fortuna and Suwabe as Cain Nightroad
- In Vampire Knight, with Minagawa as Ruca Soen and Suwabe as Akatsuki Kain
* Suwabe has been known to voice wealthy characters, such as Kyoya Ootori in the drama CD of Ouran High School Host Club and Atobe Keigo in The Prince of Tennis.