You can find the plugin needed to get the launch options by downloading frosty version 1.0.6.2,extracting it, open the plugin file in frosty mod manager which is where you'll see LaunchPlatformPlugin, move this plugin to the newest frosty mod manager, in the plugin file. I also recommend getting frostyfix. After that go to the frosty mod manager settings and you'll see launch options. With frosty fix go to settings and you'll see a few options. Also I suggest getting datapathfix as well,it goes into the plugin folder too.
Frosty fix settings:
Frosty installation is for where you choose the path to your mod manager
Custom Game is where you choose the path to your game exe
I hope this helps if you haven't found a solution:)
Links:
https://github.com/Dyvinia/DatapathFixPlugin
https://github.com/Dyvinia/FrostyFix/releases/tag/v5.3.0
Version with launch plugin: https://github.com/CadeEvs/FrostyToolsuite/releases/tag/v1.0.6.2
Newest version: https://github.com/CadeEvs/FrostyToolsuite/releases/tag/v1.0.6.3