Floogle has recently released v1.2.0 of Red Viper, the amazing Virtual Boy emulator for Nintendo 3DS, which introduces local multiplayer on supported titles like Mario’s Tennis, Hyper Fighting or Virtual League Baseball 2!
Added local multiplayer
Accessible from the main menu
Two nearby 3DS systems can play Virtual Boy games together
Games can be loaded from the SD card, or downloaded from the host system
Forwarders can only play the game they were configured with
Save data is saved and loaded per system
The input buffer can be manually adjusted: higher values may be more stable in noisy environments, but incur longer delays
Because both Virtual Boy simulations are ran on both 3DS systems, games may slow down sometimes if either player is using an old 3DS. The following games are confirmed to play well on old 3DS: