Korean anti-aging skincare for 40s - retinol alternatives?

I am in my mid-40s and starting to see more noticeable signs of aging - fine lines, loss of firmness, and dull skin. I have tried retinol but my skin cannot tolerate it - it gets too irritated. Are there Korean skincare products with gentler alternatives to retinol that still provide anti-aging benefits? I have heard about bakuchiol, peptides, and fermented ingredients. What Korean products would you recommend for someone in their 40s who wants anti-aging benefits without harsh ingredients? Also interested in any Korean clinic treatments that complement an at-home routine.