You can set multiple weights on AliExpress by editing the product page. First, select the product you want to edit, then find the weight part of the product to modify. You can enter multiple weights and add the corresponding price after each weight, separated by commas. This way, you can set different prices for different weights, making it easier for buyers to choose the appropriate weight for purchase.

After setting, remember to save the changes and update the product information in time to ensure that buyers can see the latest weight settings.