Well this relationship (Sword Art Online and Accel World) is still just a rumor.
But Kuroyukihime does share some close connections with Kirito, as both use a high-speed, dual-sword fighting style and is skilled in close combat.
Speaking of which, Shiroe and Kirito also share close connections as both are male protagonists who are somehow locked at an online game and has to face dire situations to get out of them.
Oh there is one contrast thing: while Kirito is known for being super fast in the online game and is very athletic in "reality" like outside the game world, Kaede Honjou (Maple) is below average student outside the game world and her avatar adopts a tanking and counter striking style.
All four characters prefer black clothing and are also leaders / "guild masters" of their respective online game clans or worlds. (Shiroe is the Guild Master of Log Horizon, Maple the guild master of Maple Tree, Kuroyukihime the leader of Nega Nebulus, and Kirito (Despite given high regard in a clan as he joins a few) is the Star King during the two hundred years worth of time in Underworld)
My list can go on but I am about to work soon and I have a bunch of calc requests and evaluation works.
I'm mostly going to wait until you've finished that list, but a lot of this boils down to "they are VRMMORPG players", which when searching for applicable matchups feels a little too herp-a-derp for my taste.
Take something like my updated
Melia VS MU chart as an example, and how I recently put
Dark Queen Merlina in the tied top spot. Yes, Melia; Calista and Merlina are all 'queens of dying lands' in that sense, but the prospect of Melia vs Calista, atop the Operation Rainfall legacy MU, has their respective narratives call into question their viability as queens, either in upholding a legacy (Sorean / Consort System / Arganan legacy etc.) or realising that monarchs as we see them are no longer fit for purpose (something very explicit in The Last Story, and something Xenoblade FE tips it's hat too on more than one occasion). Black Knight also has elements of this when asking 'what good a world is that is eternal / goes on forever', which is not only one of the Sonic series' nodes to libertarianism (fates worse than death etc.), but the storybook source material is what spawned these archetypes to begin with. A potential contrast is Merlina's arrogance in her role for the world that she inhabits, whereas Melia is still uncertain in altruism. Also it's not a complete stat stomp, so there's that.
Neo and Lightning respectively
Y'know, whenever I think "Neo" I keep thinking of Neo Politan from RWBY. But I get it, it's the Matrix, and while I used to think
that initial suggestion was hella cursed, I've warmed to the idea somewhat when considering the implications for our near future. Still haven't watched the Matrix though, so jury is out on whether it's
really going to bolt up my list of favourites.
Lightning, though... y'all already know my stance on that...