Hey Volunteer Here!
Bedrock isn't supported right now in any shape way or form, additionally, itemsadder does not come with a way to display your font images on anything like the TAB menu, it is ultimately up to you how you wish to implement the images wherever you want them.
You can display these images in most places using %img_FONTNAMEHERE% or :FONTNAMEHERE:, these are examples of course, use your own font names!
If you want my personal recommendation for adding images to tab, i use the plugin literally named TAB, it works for me!
Good Luck and let me know if you have any more questions!
