Hello,
I followed the official example for key sequence as text expansions but even that didn't work properly and it showed erratic or unpredictable behavior.
As in the screenshot I add a basic sequence `\\dd`
I use it a lot with VSCode, so that's probably not it. I'd recommend to first test with some visible action like "show hud" to check whether your key sequence or the action is causing the problem
//edit: ah in your video it seems like the key sequence is triggering ok but the action is not being executed. Does cmd+v work in your vscode? (When pasting, BTT basically just presses cmd+v). Is there anything special about your keyboard layout?
does the paste text action work with other BTT triggers for you (e.g. standard keyboard shortcuts)? I can't really think of a reason why this wouldn't work.
it kind of sounds like some timing issue, maybe a conflict with some other app? Could you try to add a small "async delay" action before the paste? (0.1s)