HI, you can shiplap these, but you will want to use liquid nail adhesive rather nailing them. Make sure the walls are smooth and sturdy, so patch if you need to prior to starting. Here is a link to guide you to installing without nails

https://foxhollowcottage.com/how-to-diy-a-simple-shiplap-planked-wall-with-no-nails.html

Hi! You need to make sure the plaster is tight to the lathe if you are going to leave it in place. The shiplap will need a sturdy surface to be attached to. After the plaster is tight, level it out by using furring strips. Here is a product I've used in the past when plaster that was left in place:

https://www.amazon.com/d/Flat-Washers/Plaster-Washers-Box-of-100/B008AY2MS6/ref=sr_1_36_sspa?ie=UTF8&qid=1546468695&sr=8-36-spons&keywords=plaster+wall+fasteners&psc=1

There have been several discussions on this subject, see if you find them helpful:

https://www.hometalk.com/33358126/q-how-do-i-shiplap-over-plaster-walls

https://www.hometalk.com/38134342/q-how-to-put-shiplap-on-plastered-walls

Found these too, see what you think?

http://www.theschmidthome.net/old-plaster-walls/

https://thecraftsmanblog.com/how-to-hang-things-on-plaster-walls/