I don't think scripts are automatically enabled, unless you specify during startup.
from mpv --list-options
:
--script alias for --scripts-append (CLI/config files only)
--script-opts Key/value list (default: )
--script-opts-add
--script-opts-append
--script-opts-set
--script-opts-remove
--scripts String list (default: ) [file]
--scripts-add
--scripts-append
--scripts-clr
--scripts-del
--scripts-pre
--scripts-set
--scripts-toggle
--scripts-remove
Possibly use a GUI that allows you to permanently set startup-options that way, such as SMPlayer.
Be easy enough to alias your mpv command in .bash-aliases
but I'm guessing you're on Windows because of the directory name...
alias mpv="mpv --script '/home/sketch2/Programming/Scripts/launched.py'"
a TSR that looks for launching, such as Devilspie2 would do it. Generally used for resizing and putting apps in locations you like. Something like that could be programmed to auto-run your mpv script. That might be Linux only, so you'd have to hunt for something similar in (assuming) Windows. Maybe it runs through their Linux-subsystem, I don't know. Doubt it, probably polls X in ways that windows wouldn't expect.
Are you gonna use it all the time, or just once in a while? Can you just have your script running in the background, and have it check for a running instance of mpv every 30 seconds or so? That's essentially what a TSR does.
https://github.com/mpv-player/mpv/wiki/User-Scripts
Edit:
I just realized there's an mpv.conf
-- that's where you'd set it.
I don't know where it's stored on Windows, but on *nix it's in ~/.config/mpv/
Literally just commandline-parameters followed with what you set them to. Comments are #hashed out.
https://github.com/mpv-player/mpv/blob/master/etc/mpv.conf