The point of this post is to close out the New 52 with a bookend of sorts. Two years ago, I created the first 52 Shake Up post to highlight all the canon immigrants that were kept around during the reboot. I've made several more posts since then, and in some cases the definition has expanded to include already existing characters that the New 52 changed radically enough to match adaptations that they basically became canon immigrants. But there are several more I missed, so I'll close out this era with an article dedicated to them.
The Riddler maintains his suit and bowler from the 60s show. Batman #23.2 (September 2013) is one example:
Killer Croc maintains his true reptilian-ness, instead of just having a skin condition. Batman and Robin #23.4 (September 2013) is one example:
Alfred continues to have raised Bruce after the Waynes died. This example is taken from Batman #49 (February 2016):
The Hall of Justice appeared in Justice League International #1 (September 2011).
The Global Guardians were mentioned in Justice League International Annual #1 (August 2012). I'm not aware of their formation ever coming to pass.
Adrianna Tomaz appears in Justice League of America #7.4 (September 2013), which sets her up to become Isis. As far as I know, this never came to pass, either.
John Stewart still has a military background, as evidenced by this cover to Green Lantern Corps #25 (November 2013):