Some things of Hajime don't have vectors to reflect, like the mind manip of his artifacts on the after stories key, his spatial artifacts honestly don't know if would be affected by the vector manip. In this case the more dangerous haxs from Hajime to Accelerator would be things like his Intimidation (fear and maddness) since his bloodlust is pretty potent (he can make people
faint with a glance, make them
unable to breath, have
blurred vision, get
insane, and generally speaking it can make them feel phisycal impacts despite there not be any physical force, he once also made a ghost
forget her grudges despite be unable to kill her and another time when he made a robot without conscious
feel hit with physical pressure, made an AI hallucinate that the space was creaking and made another AI pray despite be at the other side of the world with an absurd advantage over a super nerfed Hajime), so Accelerator would be ****** if he don't have a potent resistance to fear manip (which I suppose he don't have since the profile don't list anything like that). In case Accelerator have an answer to this things Hajime could use his stealth to get a chance to fully analyze and develop countermeasures against Accelerator (he could actually do that in the middle of combat, but the stealth would let him take more carefully his time).
Now, since the match was changed to After Stories Yue then I will say that this is probably an stomp, and that's because she can do practically all the haxs from the verse with a thought (well, with a word in the case of word based abilitites like Divine Edict), he don't seem to have resistance to soul manip (specifically speaking her Divine Edict) which is the main thing that Yue use in this key as starting move, similarly he don't resist her mind manip, memory manip, fear manip, pain manip, time manip, organic manip, info manip, power null, etc. From the wiki viewpoint Yue is effectively the most broken character of the verse do to how absurdly haxed she is and how potent her things are compared with most of the other characters, and considering how Accelerator lack a resistance to all her haxs things would be pretty stompish.
Additionally, Accelerator don't really have a way to put down either Hajime and Yue with the automatic and infinite revives, so even if he could somehow overwhelm he will eventually fall from exhaustion.