Depends on thetype of recession but usually non-discretionary purchases tend to fare best. Look for businesses where demand is highly inelastic and barriers of entry are high

Any business - consulting and/or operations - that can assist with increasing environmental regulatory compliance requirements & sustainable waste solutions that help companies attain their sustainability/ESG goals should do OK. Especially if those companies have certain permits, training, certifications, track record, etc. However, almost no business is bullet proof so planning ahead is imperative. Good leaders and teams will find a way.