Add the pack to your resource packs folder, and a world's datapack folder to replace copper in the bucket's crafting recipe. I wanted to make another pack, but I didn't have the author's permission to reuse their textures. Which I am actually grateful for, because now I have made a much better pack that does something similar.
Backwards compatible with most versions. The textures are most likely compatible at least as far back as 1.14. Should you want a different axolotl bucket, just delete axolotl_bucket.png and rename the one you like to axolotl_bucket.png
Obviously the datapack only works in versions with minecraft:copper_ingot
This exists because no where in the name do buckets claim to require iron. Only the crafting recipe and texture suggest iron. And that is mostly because copper didn't exist when buckets were made.

Playing with More Axolotl Variants Mod and Optifine or Axolotl Bucket Fix? Use my texture pack also found Here:
At the bottom is a link to the copper version of the pack. It is not updated like the regular version of the pack, but I will get to it shortly.

Bedrock Version Here: https://www.planetminecraft.com/texture-pack/1-19-copper-buckets-resource-and-behavior-pack-bedrock/

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NOTICE OF USAGE FOR THESE TEXTURES:

These textures are based on original Minecraft assets. You are free to use, modify, and redistribute them within the terms set by Mojang's guidelines for resource packs. Full reuse is permitted, respecting Mojang's policies.

Please ensure proper attribution to original authors where applicable.

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