I haven’t used liquid glue yet but have been using glue sticks. It’s my goto for PLA on the Bambu Cool Plate. I am not certain but the way people talk about the liquid glue it functions much the same - a release agent that helps the first layer stick.
There’s been a number of discussions of glues and sticks here, and the build plates and filament product pages all mention if glue of some sort helps on certain build plates. I don’t think glue is appropriate for all plates and filaments so be sure to check.
For me with PLA on the cool plate, glue stick just works.