Robin - Dylan O' Brien
Raven - Mary Elizabeth Winstead
Cyborg - Ray Fisher
Starfire - Nina Dobrev
Beast Boy - John Karna
Mad Mod - Joseph Morgan
Blackfire - Tristin Mays
Slade / Deathstroke - Joe Mangiello
Trigon (his vessel) - Jon Bernthal
Brother Blood - Paul Wesley
Kid Flash - Robbie Amell

In the 90s/early 00s:
Starfire- Alyson Hannigan:
Cyborg- Will Smith:
http://vignette3.wikia.nocookie.net/austinally/images/d/df/Teen_Titans_Cyborg_(2).png/revision/latest?cb=20140112044346
,
https://kyleighmontgomery.files.wordpress.com/2013/04/wilkinsirobot.jpg
Present day:
Robin- Tyler Posey:
http://vignette4.wikia.nocookie.net/teentitans/images/8/86/Robin_.jpg/revision/latest?cb=20150703043509
,
http://daman.co.id/daman.co.id/wp-content/uploads/2011/11/Tyler-Posey5.jpg
Cyborg- Ray Fisher:
http://screencrush.com/442/files/2014/10/fisher-cyborg.jpg?w=720&cdnnode=1
Raven- Rooney Mara:
http://images-cdn.moviepilot.com/images/c_scale,h_493,w_690/t_mp_quality/fp5d4i9wsx7jpch65pab/top-5-easter-eggs-in-justice-league-vs-teen-titans-that-reveal-more-about-the-new-dc-an-914952.jpg
,
http://www.imdb.com/media/rm129869568/nm1913734?ref_=nmmi_mi_all_evt_2 0
Terra- AnnaSophia Robb:
http://vignette2.wikia.nocookie.net/vsbattles/images/1/10/Tumblr_inline_mgzkz0sBh41r5ykii-1-.jpg/revision/latest?cb=20141117002213
(ctrl +),
http://coolspotters.com/files/photos/1031028/annasophia-robb-and-lacoste-womens-l658s-sunglasses-gallery.jpg?1365928001
Blackfire- Emma Stone:
http://vignette2.wikia.nocookie.net/teentitans/images/6/66/030.jpg/revision/latest?cb=20080523082015
,
http://www.taaz.com/images/B3284EEC601889A2CAC5512DE9A1FE29.jpg
Jinx- Anna Kendrick:
http://vignette1.wikia.nocookie.net/teentitans/images/e/e5/JinxGood.jpg/revision/latest?cb=20130817012753
(ctrl +),
http://i.dailymail.co.uk/i/pix/2015/02/21/25E306C100000578-0-image-a-42_1424483327379.jpg
Bumblebee- Lupita Nyong'o:
https://s-media-cache-ak0.pinimg.com/736x/5f/3a/bf/5f3abf11d7c32c810879dc3f234e72e0.jpg
,
http://moda.atarde.uol.com.br/wp-content/uploads/2015/09/lupita-nyongo-vogue-cover-october-2015-10.jpg
Honorable mention: Emma Watson as Starfire.