We shall have to keep our eyes glued to every DC TV show for the planned
vague reference to our favorite team!
There aren't all that many.
My best guess would be the CW's "Legends of Tomorrow", a show themed around time travel. So, a nod to the Legion is a no-brainer here.
Less likely, but still possible, would be CBS's "Supergirl". Having Kara meet the guy that she'll eventually fall in love with and move to the 30th century to be with would make for an interesting moment, even if she only learns of this as a passing reference. More of a "say what?" moment for Kara. Brainiac-who?
Less likely would be "Arrow", which is grounded in the here and now, or "Flash", which seems to be fine with exploring other worlds of the multiverse.
Least likely? "Gotham", of course. Watch the show, you'll figure it out.