It is likely for the same reason that USB A-to-A cables aren't common: host devices should always use different connectors than slave devices. The reason is that serious damage to the USB controller is possible if you plug two ends of a USB A-to-A cable to two USB ports on a host device (like into your computer). It is against the spec for a reason.
A-to-A cables (or cables as you describe) should not exist according to the spec, simply put.
Answer from Ben Richards on Stack ExchangeMini USB to Micro USB Question.
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It is likely for the same reason that USB A-to-A cables aren't common: host devices should always use different connectors than slave devices. The reason is that serious damage to the USB controller is possible if you plug two ends of a USB A-to-A cable to two USB ports on a host device (like into your computer). It is against the spec for a reason.
A-to-A cables (or cables as you describe) should not exist according to the spec, simply put.
My guess is, that devices with a Micro USB connector do not typically offer USB-Host functionality. So even if you were able to connect two devices with Micro USB ports, there would be no additional benefit/nothing to do with this connection.
But as I said, it is just a guess..
Probably not.
USB charging cables typically do not have the data pins connected.
In fact there might only be two conductors (just for power) in the cable instead of the required four conductors for USB just to save on cost. (I have actually taken a USB charger apart.)
Whether you will be able to "transfer data" to/from your tablet depends on what you want to connect to your tablet and maintain the USB host-to-device hierarchy.
As is, you're asking an XY question.
No, you can't.
There's literally one specific scenario where this can work
You have a USB OTG adapter - which is not exactly the same as a USB micro adaptor. These are less than 2-3 dollars online, maybe a fiver if you get a fancy one.
One device is able to act as a host, and the other as the target.
That said, any attempts to splice your own from two cables without knowing these things will just result in 2 broken cables.
For extra fun - the quality of cables ranges broadly - from the cost engineered cables sawdust has mentioned. You're better off getting the USB OTG adaptor, and testing with a known good data capable cable over splicing a pair of perfectly good cables (or 2 terrible ones, or any mix of those).
TL:DR Am I able to desolder a mini usb cable and solder in a micro usb cable matching pin to pin from the old cable to the new one?
I'm probably over thinking the situation but just wanted to ask for verification. I was given a free hard wire kit for my dash cam from my dashcam company since they no longer sell the connector type kit for my camera (they sell ony USB-C kits now). I asked for a Micro USB kit but they sent a Mini USB kit instead. Based off how long it got here I'm afraid a new kit would take too long to get here before I needed it. I popped the case to the mini kit open and saw three wires being used. I shot the wires and the picture below is what I found. My question is am I able to get a 5 pin micro usb cable and match pin 1 on the micro to the mini and so on?