Urban Art Association

B&Q do a metal self drive plug (their name!) but i wouldnt say minimal wall damage. They have been rock solid for me though.

You want these things. They will hold a heavy weight:
www.screwfix.com/p/easyfix-self-drill-plasterboard-fixings-metal-32mm-100-pack/2422H?kpid=2422H&cm_mmc=Google-_-Product%20Listing%20Ads-_-Sales%20Tracking-_-sales%20tracking%20url&gclid=CjwKEAiA94nCBRDxismumrL83icSJAAeeETQt31wXCg4y8Eif8pAcPD8NnrhImIKpXmLfSwG4NRxhxoCkL_w_wcB

I've used these on a number of heavy works in two different homes and they've worked flawlessly. A bigger hole in the wall than a nail for sure but your art isn't laying on the floor at any point either with a huge chuck of dry wall. When i left it was easy to caulk and paint over. Better still, i reused the same hanger supports on the same pieces at the second house. Highly recommended and should point out that they were installed on the first go around by professional hangers.  I wanted someone who knew their stuff doing it the first time so i can't take credit for it but it was easy to remove and reuse. Good luck

www.amazon.com/OOK-Heavy-Duty-Drywall-Hanger-Supports/dp/B000CSN354

Not 100% sure, but I would expect the plaster will break before these do.

Two of these will hold anything. I remember reading that one alone will hold something like 11kg easily. I got the pulling tool too.

www.screwfix.com/p/rawlplug-hollow-wall-anchors-m4-x-40mm-20-pack/54782?kpid=KINASEKPID&cm_mmc=GoogleLocal-_-Datafeed-_-Screws%2C%20Nails%20and%20Fixings&cm_mmc=Google-_-Product%20Listing%20Ads-_-Sales%20Tracking-_-sales%20tracking%20url&gclid=CNj28urN2NACFasK0wod7oAKBQ

Agreed, these are fantastic.

I've used these in the past and they have held everything (they claim 25kg). Push them in by hand, then if you want to shift bits around pull them out and you're only left with a tiny hole.
www.clasohlson.com/uk/Hercules-Plasterboard-Hooks/31-4620