is there  any plugin to change cost of items to craft

yes and no.... There is a way to change them nut not in the standard craft menu.. you would need something like craft plus to make a custum UI to display them

is that paid plugin or free one

its a paid on, it works also for like selling in game kits or other things as well by letting people use in game items (like scrap as an example) to buy/craft them

where i can buy it then and name of plugin

Name of plug in is CraftPlus, google it or pm me on discord at Razor14150#7265