We've seen the one on the bottom left before (see >>263768 ), but I will now be tracking down the bottom right one.
Cut and paste from blurb (my emphasis):
"For My Little Pony fans, IDW has a special surprise! An exclusive glitter variant cover of MY LITTLE PONY: FRIENDSHIP IS MAGIC #9. But, heres the trick: '''it contains 8 pages of material that isnt in the regular edition, featuring the Equestrian Girls!''' Fans worldwide will be clamoring to get a copy of this, and the ONLY place to read this story is in this exclusive, and the ONLY place to get it is the IDW booth at SDCC! This item is limited to 1,000 copies, with a limit of 5 to a customer. **Note Watch for the Diamond Comics variant, available to Comics Retailers at SDCC.
Another My Little Pony treat is the MY LITTLE PONY: FRIENDSHIP IS MAGIC VARIANT EDITION HC. This is the only way to get this material in a hardcover format! With a variant cover by fan-favorite J. Scott Campbell, this edition is limited to 500 copies, priced at $25, with a limit of 3 to a customer, and only available at the IDW booth."