If you want Gundams and other anime, its Japan only.
There is a SRW in English but it only serves as a collection of all the different Original characters and units that have surfaced in each SRW game. Like each SRW will have its own unique main character and mech seperate from its featured anime. There have been so many of these original characters, the company who makes it decided to give them all their own SRW.
Thus we have the games SRW Original Generation 1 and 2 on the GBA.
There are many games ranging from GBA and DS to PS2 and 360. There is no PS3 game.
The SRW series is around 15 years old.
Pic is from SRW OG.