It's odd that of the two fighting games that Psikyo developed, it's Daraku Tenshi, the one that never got released, that seems to be the most well-known. Battle K-Road is still definitely worth a look, though, as despite its psuedo realistic setting (the only fantasy elements being that two of the playable characters are cyborgs, and the final boss is a bear, plus some silly joke endings. But the mood is still realistic, and there's no fantastical or super-powered fighting techniques), it's still a game that does some interesting stuff in terms of both mechanics and storytelling.
There are seven fighting styles represented among the playable characters, with two characters for each of them. The two characters for each style are just headswaps that play identically to each other, but the only reason this setup exists is for storytelling purposes. A single player game starts with you facing against the other representative of your fighting style in a match that's implied to be the final of a tournament, with each style's first fight taking place on a unique stage. Every subsequent fight takes place on the same stage, with the time of day changing as the fights go on. The implication here is that you're playing as the proven champion of your chosen martial art, representing that art against all the others in the Battle K-Road tournament. It's a cool little touch that adds a lot to the game's atmosphere.
Mechanically speaking, there's some interesting stuff going on there, too. Special moves are performed by holding an attack button, then pressing a direction while you release. It's an input method not often seen (the only other examples I know of are Primal Rage and the SNES Ranma 1/2 fighting games), and though I've hated it in those other games, it really works well with the grounded playstyle of this game. A more unique quirk, and a nod towards the game's combat sport theme, is that whenever a fighter gets knocked down, the fight stops and oth fighters return to their starting positions. It really marks out that the fights in this game are part of a sports competition, as opposed to the unsanctioned fights in most fighting games, and it also means that there's very little scope for trapping an opponent in the corner or in some other disadvantageous position.
Battle K-Road is a game I've been playing a lot recently, and it's really a shame it still hasn't ever had a home console release to this day, as it's a really fun and interesting game that I think must have gotten lost amongst all the other fighting games that got released during the original post-Street Fighter II fighting boom. Unfortunately, its uniqueness didn't help it stand out from the crowd, maybe because that uniqueness manifests in the form of deliberately being less flashy and extravagant than all its competitiors. Still, you should definitely give it a try if you get the chance, it's an excellent game, that's aged a lot more gracefully than a lot of its contemporaries.