9xbuddy | Savesubs
Now that you have an .mp4 file (from 9xBuddy) and an .srt file (from SaveSubs), you need to combine them for playback.
This has a paid model, but the free tier allows you to download videos and subtitles simultaneously. It is the closest one-click solution to the "9xbuddy savesubs" query for casual users. 9xbuddy savesubs
This is a command-line tool, but it does what 9xbuddy savesubs cannot. It downloads both video and subtitles in one command. Now that you have an
yt-dlp --write-subs --sub-lang en,es "VIDEO_URL"