Fairly recently, I saw an app that served the same purpose as Barrier or Input-leap, allowing you use one computer to control the keyboard and cursor of multiple. I’m fairly certain it was designed with GTK 4, or maybe 3, and it had Wayland support. I’ve had no luck getting input-leap working well on my devices, so if anyone knows what app this was (or any other options) I would really appreciate it.
Update: Despite searching for 15 minutes before posting, I found it seconds later, thanks to DDGs reddit bang. It is lan-mouse. Will leave this up in case this software comes in handy for others.
Similar functionality is actually baked into the kernel!