Through survival only potions with durations can be crafted into rings however instant effects are available through commands. The rings amplifier will be based on the potion used to craft for example: If crafted with swiftness II then a swiftness II ring will be made If crafted with swiftness I then a swiftness I ring will be made

This mod should work with potions added from other mods (although this is untested). Rings made using non-vanilla potions will simply have the name "Enchanted Ring".