A simple mod for Silksong. Hold a certain button to walk slowly anywhere. Default is the keyboard L, but you may easily adapt it to another key.
It works while the key is held, but you can reconfigure it to be working on toggle instead.
Take WalkButton.dll out of ant_of_doom-WalkButton-1.1.0.zip and put it into BepInEx\plugins.
Done.
You can change the default button by launching the mod at least once, after what it creates a config in the BepInEx\config folder. The config is called org.sealofapproval.walkbuttonmod.cfg. It's easy to change the default button, just open it and replace the L in the line walkButton = L with anything of your own choice.
In the same place, you can change the toggle/hold setting: replace hold in the line mode = hold with toggle, or vice versa.