For Peplexity it’s easy because they have a nice simple URL scheme. You can use this snippet:
# popclip
name: perplexity
icon: iconify:simple-icons:perplexity
url: perplexity-app://search?q=***
(The above block is an extension snippet — select it then click “Install Extension” in PopClip.)
No sure if there is a similarly easy equivalent for Claude.