If you do not have 3 mason jars, you can use any heat safe jar that fits in to your instant pot. I just happened to have a jelly jar, pickle jar and small mason jar and it all fit.
When the eggs are wet, the dye will come off easier so be careful not to handle them too much until the shell has dried.
Find it online: https://listotic.com/dyed-easter-eggs-instant-pot-8-minutes/