If you want to do economics, do maths. Maths is an extremely versatile subject which goes with many degrees (not just STEM, this includes economics, geography, psychology, etc). However it is not easy so I wouldn't pick it unless you're getting a grade 7-9 to be honest.
Also language A levels look fantastic no matter the degree. Definitely pick a language if that's what you're good at and interested in.
Aside from that, you have a lot of creativity. Most degrees don't really mind what A levels you did as long as they're somewhat relevant. Economics goes well with geography and business while politics goes well with history or sociology or even philosophy. Don't overthink it, choose subjects you like as its mostly about grades over the subjects you choose.