Meet Project Patchouli, an open-source drawing tablet project to 'build your own tablet from scratch'
You will need some electronics knowledge, though.
(Image credit: Yukidama on YouTube)
For something intended to mimic good old pencil and paper, drawing tablets and the tech behind them are surprisingly complicated. If you fancy a crash course in how they work and want to build your own from scratch, I have the open-source project for you.
Project Patchouli from designer Yukidama is a project to "build your own EMR tablet from scratch". As helpfully laid out in Yukidama's YouTube video, an EMR tablet is one that uses Electromagnetic Resonance that sends a signal to a tablet, which is then translated by the tablet. It's a quick and responsive bit of technology, but different pen vendors work off different frequencies, which can impact compatibility.
Build your own EMR Tablet from scratch - YouTube 
Much of the hardware blueprints are in CAD files, which means (for most) having to send those files off to get created by a circuit board manufacturer. A project like this won't be done on a whim, but it's still rather impressive.
Over on the Project Patchouli Discord, Yukidama has said that they are looking into documentation so that the non-initiated can also replicate the project and has said, "Please let me know if there's something you want to know in particular, so I can include them in the guide." Though I'm tempted to say 'well, all of it', I do think the YouTube video does a good job at explaining the background of EMR tech and why artists use EMR tablets.
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In a sense, one could look at this more as a proof of concept than a replacement for a drawing tablet. Modern drawing tablets will have all kinds of neat software and hardware handshakes like tilt control or high-pressure sensitivity, and they will be a good bit bigger than the rather small tablet Yukidama is using. But what makes it interesting is that the tech is there and ready to use. It being open-source allows someone else to pick up the project and run with it.
Still, if you have the will to make one, and don't mind contacting a PCB manufacturer of some kind, this not only seems like a solid way of getting around pencil compatibility issues but also a way of learning about tech that you may not have put much thought into until now, I know It's certainly made me a little more appreciative of drawing tablets.
