I see this is a dead post, but I am interested as well in a plugin like that. I'll attempt to explain the battle system.
In the top right are the foes you must fight, and the bottom left are the characters. Health is shown with a character's icon in the top-left corner, also showing any status effects on them based on expression. When it is a player's turn, 4 options (in SMRPG it shows the X, Y, A, and B buttons) for items, attacking, special, and fleeing appear around their head. When an option is pressed, it shows a detached menu based on what you chose, then an arrow pops up to ask which entity you would want to use it on. When a foe attacks, the characters are able to block them if the action button is pressed at the right time. While it will not stop damage, it greatly reduces it. Likewise, players can boost attacks and special moves if the action button is pressed at the right time.
In case your internet allows, I provided 2 screenshots.
