There are several ways to deal with this situation:

1. Find the source of goods and ask the supplier

2. Estimate the weight of the product and set the price before listing. Generally speaking, it is not very expensive to add weight to many sites. For example, in Taiwan, the shipping fee for 300 grams and 400 grams is actually the same, but sites like the Philippines and Brazil require careful pricing.

3. Sampling

Combining the above, the second one is the most commonly used. Cross-border transactions are generally light and small, and the weight range is easy to estimate.