It would be great to have a plugin that make some blocks to spawn a item, example for me, I want example a block (that we could set on a config file) to spawn a Firework, not the object that a player can take but to launch a firework...I don't know if the plugin has been already made
What do you mean by "blocks to spawn an item"? Mob spawners dropping the item or do you want a block to act as a dispenser? To shoot off certain items, in your case a firework/fireworks? And No I dont think suck plugin has been made.
It can probably be coded, im not sure about this one. Maybe spawn the item as a projectile entity? Or spawn a firework at every X seconds using the block's XYZ coordinates.
Im not a good coder xD, I will look at some plugins code to see how they are made (plugins that launch items) or ask