I put holes in walls for art and patched them for part of my living. Most of my past working life. Art galleries were my clients.
Decide how heavy your piece and whether plaster, perhaps separated from the lathe behind it, can hold it. If you are good to go?
Fools suggest covering plaster with tape to prevent it from fracturing when you try to hammer fasteners into it. I loved the calls I got to come fix it!
These masonry things sometimes work on plaster walls but you must tap, not pound them in place. They do not hold much. There is actually a tre-cool system for mounting art to brick now that is non invasive. Spring loaded clips grab the top and bottom of brick and provide a more or less mid brick hook.
For permanent home installations I used flat picture hangers, screw anchors and screws. You will need to invest in good masonry bit and a drill.
Measure carefully so you come close to where you want the art to hang. Check with a stud finder or with a tiny drill to see if you need to drill for an anchor. If so, you have a pilot hole for the screw through the hanger into the stud. If not, use your masonry bit to drill for the screw anchor. Put it in place. Attach your hanger. Toss the screws that come with most of the anchors and buy some good US forged and plated ones. The Chinese crappy ones strip on you instantly even in a plastic anchor.
I have yet to damage the oldest of plaster walls with a thin masonry bit. Not saying I have not been lucky.
If you missed where the art should be by 4 or more inches? Your an idjut. If it is off just a bit, tweak the framing wire.
Obviously horizontally long pieces need more than one hanger. Heavy ones two.
If the piece is exceptional heavy, you must not rely on the lathe and plaster (or drywall for that matter) to hold it.
Please promise me! No adhesive to hold so much as a temporary sign up on painted walls ok? I will fly to wherever you are and fix any holes you make in walls but I hate adhesive damages. And those peel and stick things are pure evil.
My other fave system for things like kid posters. Screw heads and super magnets. Poster sizes do not change but tastes and trends do. I actually use the system for large pieces of paper and fabric art. Screw heads down flush with the surface. Use screw anchors. Then buy a pack of super magnets. Mount the poster, attach it with magnets. Nice surface WITHOUT ADHESIVES. Easy to repair holes.