Remove Crying obsidian and modify loot table

Is there a way to remove crying obsidian from ruined portals via datapack? And can you standarize loot, like every ruined portal chest has at least 2 obsidian? I know you can modify the loot table, but I dont want there to be like 10 obsidian in one chest. And can you standarize piglin trades so that they are the same on every seed?