After getting Nautica from the Speed boxset, I was thinking about other times characters originally designed without a toy that ended up later getting one. Did some research on TFWiki, and I think I've made a complete list. The year they appeared and the year they got a toy, along with how long it was between the two. Anything I've missed? Dion: 1985-2005 (20 Years) Moonracer: 1985-2006 (21 Years) Alpha Trion: 1985-2007 (22 Years) Acid Storm: 1985-2008 (23 Years) Elita One: 1985-2009 (24 Years) Straxus: 1985-2010 (25 Years) Gravedigger: 1985-2012 (27 Years) Chromia: 1985-2014 (29 Years) Tornado: 1985-2014 (29 Years) Devcon: 1985-2014 (29 Years) Nightbird: 1985-2016 (31 Years) Wipe Out: 1986-2012 (26 Years) Impactor: 1986-2013 (27 Years) Ferak: 1986-2014 (28 Years) Scrounge: 1986-2016 (30 Years) Sentinel Prime: 1988-2016 (28 Years) Jhiaxus: 1993-2003 (10 Years) The Fallen: 2003-2007 (4 Years) Drift: 2008-2010 (2 Years) Grindcore: 2008-2012 (3 Years) Slipstream: 2008-2013 (5 Years) Roller (IDW): 2012-2016 (4 Years) Minimus Ambus: 2013-2015 (2 Years) Nautica: 2014-2017 (3 Years)
If you want to count 3rd party, Mastermind Creations has done three of the Decepticon Justice Division characters.