One could try "printing" 1.3mm EL wire using a nozzle of similar diameter, low enough temperature to only melt its outer PVC layer, and thick layer height so that its core isn't squished. And it would of course have to be vase mode.. I'm not saying it would work, but it might be an interesting experiment.
Maybe, but phosphorus is pyrophoric and it seems like you'd risk stripping the PVC off by running it through a nozzle, especially at the end of the nozzle where the material would bend sharply.. There's not a lot of phosphorus there, but you could have a tiny fire in your nozzle.
Depending on what you're trying to do, you can get EL panels and EL tape which can be cut to custom size & shape, and the part connected to the wire will still work (even with holes punched through it).
It's also possible to make EL paint and coat surfaces with it, though definitely an involved process and not cheap. Lumilor sells EL paint kits which were used in this youtube video to coat various surfaces. This article from Hackaday specifically mentions painting 3D printer objects, but I didn't see any examples.