You can get some pretty close sounding guitar sounds from a simple wav instrument and using really good guitar effects vstis. I have 2 electric, 3 accoustic - and if I use a very simple serum setting (or other more basic saw/triangle synth), with https://www.native-instruments.com/en/products/komplete/guitar/guitar-rig-6-player/ (which is free - I use it with my guitars) - it sounds pretty close to the real thing. I sometimes do this as a place holder before actually playing it with the guitar to see if it "fits" before recording. If you tweak it enough, (velocity settings, and some other synth manipulation), you could make it harder to determine if it's authentic.
I don't have a bass, so I recently did this to make it sound like a metal bass guitar. The fake bass with the live guitars, it sounds spot on. Now I just need to get better at playing guitar ?