Hi, have you discussed your subject choices with your teachers and/or IB co-ordinator, or even your school university counsellor? A regular IB Diploma requires you to pick subjects from each Group, with the exception of Arts and if you choose to skip this Group, you pick a second subject from Group 3 or Group 4. Therefore, you wouldn't want to be picking two languages in addition to HL Eng A LL as this does not meet the Diploma requirement.
Learning from my friends who are either now in law schools in the UK or have received offers to study law this Sep at UK law schools, the 2 key HL subjects have been Eng HL (which you have chosen) and a strong essay-based subject like History HL. Friends with these 2 subjects have received great offers, which are not enough in itself as they too have to do really well in their LNAT MCQ and Essay. So I would say, choose HL History over HL Econs any time, but if you do not like History, there is no point choosing it.
ESS is typically regarded as a 'weak' subject by top universities. If you can really avoid it, consider choosing another SL instead.
All the best with your choice.