As for the manufacturing process, look for watches that were produced with minimal waste.
You can also look at ones using renewable energy sources.
This information is available with a little research on the company.
As well as this, you can look for certifications like Fair Trade or Forest Stewardship Council (FSC) and Global Recycle Standard (GRS) for materials.
Additionally, durability is an important factor, watches that last longer can significantly reduce the environmental impact in the long run.
This is much better when compared to having to replace a watch frequently.
It is also crucial to consider the disposal and lifecycle of the watch.
Being aware of the recycling programs offered by the company and options for end-of-life products.
In this way you can avoid contributing to electronic waste.
You can also consider second-hand.