you could use a timed trigger for that and use the "Run Apple Script" action
tell application "BetterTouchTool"
export_preset "some-example-preset" outputPath "~/Documents/preset.bttpreset" includeSettings and compress
end tell
Or via "Run Real Java Script" (this one adds a timestamp for the current date to the filename):
(async ()=> {
let result = await export_preset({name:'the_preset_name', compress: 1, includeSettings: 1, outputPath: `~/Downloads/thePreset${Date.now()}.bttpreset`})
returnToBTT(result);
})();