The Evolution Stone Upgrade Template would be an opalescent-colored template that can be dropped by Epic, Legendary, and Ultimate bosses. Possibly Rare Bosses too if the templates are too hard to find. The template can also be found in any of the Ultra Space loot tables and possibly the Beast PokeLoot. This one upgrade template can be used in a smithing table with a Netherite item and your choice Evolution Stone to create the Evolution Stone set piece you want. In order to duplicate the template, you use the same recipe as the other smithing templates, and the center slot uses any Evolution Stone.
When I was playing the game on 1.20, I noticed that Evolution Stone tools and armors didn't quite seem to be where they needed to be in terms of how easily they are obtained:
- You can get a pickaxe that is better than Diamond as long as you happen to get three of the same Evolution Stone, which means the tools could be obtained very early in the game and allow the player to skip several tiers (though Diamonds are very easy to find in 1.20 thanks to the cave overhaul). If you just want the effect, you just need one to craft a shovel that grants you the effect.
- The armors, on the other hand, require 24 of the same Evolution Stone to gain the effects. On one playthrough I did, I wanted the Dusk Stone armor set so I could get the Saturation effect, granting fast healing and endless sprinting without needing to eat. It took so much time to collect all the Dusk Stones that I ended up just keeping my Dusk Stone armor at my house because I didn't want to fall in lava and lose it. The only Evolution Stone armors I felt comfortable using were ones that are found in loot tables or on armor stands. Plus Water Stone armor, but mainly because ocean exploration is fairly safe.
This suggestion would ensure that the tools are later-game items as well as lower the Evolution Stone costs of crafting the armors. You can't just create a high-tier tool if you happen to get the same three Evolution Stones, because you would also need to get several later-game things:
- The Evolution Stone Upgrade Template from a high tier boss or Ultra Space (which itself would be late game if my recent Ultra Wormhole suggestion was added). You can duplicate it like any other template, but you still need to get it in the first place.
- The Netherite Upgrade Template, since you'd need to get a Netherite tool or armor piece to get the version for the Evolution Stone of your choice. This would require going to the Nether and finding a bastion remnant, meaning the player would need to create a Nether Portal.
- A Netherite Ingot. In order to get these, the player would either need to find ingots in a bastion chest or craft the ingot from netherite scraps and gold ingots. The best sources for Netherite scraps would be bastion loot or 4-5 star raid battles. The latter is most commonly found in Ultra Space due to the 3-star minimum and the larger number of raid dens. The ancient debris in the Ultra Plant could also be a source. They could also be obtained in ancient debris found in the Nether or rarely in the chests in the Ultra Crater geysers. The player might get enough Netherite for one or two pieces in the Overworld if they find and beat high tier raids, but most likely they would go to the Nether or Ultra Space to obtain Netherite.
- A Diamond tool or armor piece that will be converted to Netherite version and then the Evolution Stone version. This means that the player can't craft an Evolution Stone tool to skip Diamond, since it is now a requirement for getting it.
If this change is done, then the stats for the Evolution Stone sets should be modified to be at least equivalent to Netherite, since they are upgraded from it. They would each be able to mine anything Netherite can, and most likely durability and armor values would match too. Mining speed, armor toughness, and enchantability may differ from Netherite, but would most likely be better.