The hookshot glitch is caused by ToonLink having different rel data from Link so you need a Link rel thats goes over toon Link's ecause I believe the LXP Younglink is based upon a YoungLink moveset on the brawlvault that I have in a private BrawlEx build In there I just used Link's rel.
Thread for Rel's over other charactershttps://smashboards.com/threads/p-m-plug-play-rels-module-files-want-to-port-ridley-come-here-modding-faq.416959/
Click on Link's icon, download the file and rename the rel to ft_Toonlink. Note the rel's
will crash the game if you have any Project M build that has BrawlEx in it.
2nd problem in a nutshell is because YoungLink uses Link sound bank and the 9.sawnd file from the LXP build so you'll need that file for his sounds and the sound bank modifier code to change ToonLink's sound bank id.