It would be important to check if the company has a ESG policy and framework, what is the work that they have done on ESG as the policy should not merely be on paper but put into action and there must be genuine committment. It will also be a good idea to have an external agency conduct an audit on ESG for the target company. Also look up on the ESG reputation of the company, if any environmental violations have taken palce, any legal matters in the court on ESG/governance etc.