Which is better,work to eliminate the risks or transfer it to third parties through insurance?

Generally the answer is "it depends". It depends on 1- types of risk 2- feasibility study of risks. For example, Sometimes the activities have risk are important parts of project then it is impossible to use AVOID strategy then you have to use other strategies like transfer. If they can be avoided then we should investigate about the cost of avoiding because avoid strategy means changing of PMP that it need to use more resource if the cost of avoiding is less than risk impact, Then it's better to use avoid

Whenever you are not able to avoid the risks , it better to transfer it to an insurance company , providing that applying any method to minimize the risk from your side will lead the insurance company to reduce the premium rate and the overall cost of insurance.

Thanking you

its depend on the cost of risk transfer, expected loss, risk appetite, cost of risk internally control