Invisible Armor & Elytra Version 1
This Resource Pack makes all armor invisible including elytra. Your armor will still be there and the inventory texture won't be changed, just the model.
This Resource Pack is for 1.16, 1.17, 1.18 and 1.19

If you are using 1.17+, it will say it won't work because it is made for an older version of minecraft. It will still work though so just use it anyway and it will be fine.