What can I do or where can I sell ?

we do not have info on who you could sell this to you can check with electriacal contrators in your area - here is info for you and it seems the plastic is for protection and shouldn't be removed from the wiring

https://www.hunker.com/13414152/why-are-electrical-wires-covered-in-plastic

https://www.toppr.com/ask/question/why-rubber-or-plastic-used-to-cover-electric-wires/

You might be able to find a plastic recycler that you can sell the plastic to. Check for plastic recyclers in your area and get in touch with them.

This idea may be too far "outta the box" but have you considered using the wiring to create wreaths? Seems to me the product could be used to make wreaths that would look similar to grapevine wreaths. Maybe a new creative business?

Contact your county to see what they recommend.

Check with a recycling center in your area.

Agree with Ann contact your local recycling center and ask them what they accept and what they don't accept.

Will you be able to remove and deliver the plastic to a dump for recycling?

Contact your church, clubs or organizations to find people to help you with this if you are not able to do this yourself. Family and neighbors might also lend a hand.

Does seem sketchy to remove the plastic near wiring. Why was it there in the first place? Is it worn or torn?

In the past, I've used wiring to hang a bird feeder for my parents. I would think of other outdoor items that might need a sturdy means of securing.

If you have enough, you might put it on facebook marketplace to sell.

I doubt the plastic can be used in 3D printers. Those plastics are specific formulations for 3D printers. Best would be for them to be recycled by a plastic recycler and more likely be reused for wire insulation or blended with other chemicals for other uses.

https://www.thongguan.com/types-plastic-used-3d-printing/

How much do you have, as in length, or weight?

Some recycling depots pay for recyclable materials only if they are in very large lots.

You could try Facebook Marketplace or the materials section of Craigslist to sell it.

You might be able to contact your local dump and ask them for the number to find out what and where to recycle in your area.