Of the Major fighting game series, I think Tekken is the one I haven't played in the longest. Not counting KOF/FF because I've never played them so it's hard to count them.
Street Fighter: Street Fighter 6 like... just the other day.
Mortal Kombat: MK9? 10? like 9 years ago.
Guilty Gear: I played Strive a few weeks ago
Granblue Fantasy: Played Versus Rising about two months ago.
Marvel vs Capcom: I played UMVC3 a week and a half ago
Soul Caliber: Played Soul Caliber 3 back in 2009
Tekken: Tekken Tag Tournament on a friend's PS2 in 2006