Getting Quickshot V joystick to work properly on other system

Welcome Foreigner!
Would´nt it be better to place this question in a ZX forum?
Before I owned a MSX machine back in the days I got a Sony MSX Joystick for my C64. The second fire button triggered a hardware reset on that computer. That was a awsome feature, when I was about to loose in a two player match, but painfull for my commodore.

ZX spectrum +2/+3 joystick ports have different pinout than Atari/Commodore ports.
But Kempston interface for ZX 48, works with Atari joystick!
Atari joysticks have 1 fire button. MSX/CPC joysticks are identical with Atari joysticks, but have 2 separate fire buttons. Also a 2 buttons CPC joystick works well with MSX because is almost identical.
So, an MSX/CPC joystick must work well on Atari/Commodore and Kempston interface but must avoid to press the second fire button. An Atari/Commodore joystick works without problems on MSX/CPC but for 2 button games, must used the keyboard as second fire button. I hope it helps.

Thanks everyone for the answers and information!

Believe it or not but I didn't get much enthusiastic responses from people regarding this joystick on a spectrum.
I always admired the design and fell in love with it back in the day while reading spanish magazines where it was often advertised (and for use with the spectrum). Sadly, only now I managed to get one but in pretty good shape.

Well anyway, I did managed to get it to work by doing some rewiring of the connections. Fortunately, the wires inside have some sort of terminals which can be pushed or pulled allowing an easy change of track on the pcb.

So, I disconnected +5V and OUT, changed the ground track and fire 2 track while keeping the directions assigned to original tracks.

As pointed out, it works with kempston interface (one trigger) and with a programmable interface I even get the three fire buttons to work (albeit only two triggers, which is already rather good for the spectrum!).

However, I still find intriguing the circuit on the pcb and what would be its use.

I tried powering it with +5V but the triggers acted the same, so I suppose it will not work on the spectrum but never mind, it is good as it is now.

Nevertheless, should anyone have one of these joysticks and use it with a MSX I would be interested to hear how it is supposed to work in fully functional glory. :D

I don't know, maybe because this particular joystick is regarded as a MSX product some people don't like to talk about it on their forum or don't appreciate the idea of it being associated with the sinclair/spectrum experience.

I have to be honest with you, I missed all the MSX story and in my country spectrums were everywhere (and later on Commodore and Sega really took off). I don't think I can even remember a place where MSX were for sale along with other computer systems. But I do remember seeing the occasional MSX from big company names when my mother went out looking for kitchen appliances in stores! It felt odd and usually there was no information available, furthermore nobody at school knew or talked about it so it slipped unnoticed.
But nowadays, thanks to magazines like retrogamer, curiosity and interest on all those systems that I missed for various reasons, has gone up and I must say I have become impressed with the originality of the MSX hardware. For example, I don't even know if it is any good but I find the Sony JS-55 Joystick a piece of artwork. Hopefully I will get one sooner or later.

That is my suspicion based on the picture of the outer box found on the page dedicated to the Quickshot V, that reads the following:

I sure wish I could understand how to make it work but I have a low knowledge of electronics. :o