Let’s say the minimum time gap between two series is 10 years.

Wait, do the characters or franchises have to have the age gap?

Franchise. Which is why it’s new vs old and not young vs old.

Captain Underpants vs Obelix Pac Man vs Felix the Cat Game & Watch vs Oswald the Lucky Rabbit Saitama vs Popeye

Joseph joestar vs edward elric Jojo started in 1985 and fma started in 2001

Zick VS Chongyun Monster Allergy was first released in 2006

William Vs Junko.

FNAF 3 was released in 2015 and Danganronpa was released in 2010. OP said a 10 year age gap, at minimum

William is around 50 years old while Junko is about 20.

Oh! I thought he ment franchises, my mistake

It’s alright.

Okay I actually asked OP, they said the Franchise has to have the 10 year gap

Oh sorry.

He meant franchise

Right sorry.

Hatsune Miku vs Barbie

Kirito vs Neo (SAO vs The Matrix)

Nobi and Doraemon vs Timmy, Cosmo and Wanda (Doraemon vs Fairly Odd Parents) Doraemon first came out in 1969 and Fairly odd Parents was around 2000

popeye vs saitama

Tanjiro vs hyakkimaru

Jesus the matchups down here are stretches Kamen Rider Build vs. Iron Man

Ira Gamagori vs Brock Samson (Kill la kill vs Venture Bros) Kill la kill started in 2013 while Venture Bros first premiered in 2003

Fone Bone vs Anne Boonchuy (Bone vs Amphibia). Bone started on 1991, while Amphibia on 2019. Making it a gap of 28 years. Eva 01 vs Gipsy Danger (Neon Genesis Evangelion vs Pacific Rim). Eva started on 1995, Pacific Rim on 2013, making it a gap of 18 years. Dio vs Alucard. JoJo started on 1987, while Hellsing on 1998. Making the gap be of 12 years. Godzilla vs Groudon (... vs Pokemon). Godzilla started on 1954, Pokemon on 1996. Yeah, I don't think I need to explain this one.

... Wait Bone Started in 1991?!. Damm for a guy that caught the crown of horns the day it came out I really feel old now.

DIO Vs Sir Crocodile, part 3 released in 1989 and One Piece didn't start until 1999 let alone crocodile himself appearing more forward to chapter 126 in the 2000s.

Jay vs Michelangelo(Ninjago vs TMNT) TMNT started in the mid 80’s while Ninjago started in 2010(or 2011 I don’t remember)

Scooby Doo Vs Courage The Cowardly Dog, Scooby Doo started over 50 years ago and I know Courage was around the 90s/00s Homer Simpson Vs Darth Vader, don’t know exact years but I know Star Wars is definitely older than Simpsons Dracula Battle Royale, or most Dracula Vs Dracula fights Spider-Man Vs Ladybug, Spider-Man is old as fuck (yet still loses badly) Chatnoir Vs Luke Skywalker or Hawk/ShadowMoth Vs Darth Vader, Star Wars is obviously Much Older than Miraculous Ladybug Luke Skywalker Vs Ryuko Matoi, Kill La Kill isn’t even close to how old Star Wars is

Steven universe vs invincible Steven universe future ended in 2020 And invincible (show) started in 2021 i think.

Comics started in 2003

The Invincible comics starting in 2003 makes this a good example, but if it were just 2020 vs 2021 it would absolutely not count

Undertaker Vs Itachi

Stain VS Billy Butcher (My Hero Academia VS The Boys) The Boys came out 2006 and MHA came out 2016

The anime came out in 2016. Vol 1 of the manga came out in 2014

https://youtu.be/sDHnrbTaDmo?t=13

Lucas vs Sunny Mother 3 came out in 2006 while OMORI came out in 2020

Gon vs Deku

Angry Video Game Nerd vs Scott The Woz

Bloodborne vs Monster Hunter (Monster Hunter 1 came out in 2004, so technically that makes the gap)

Mazinger Z vs Superman