I am wondering if it is possible to create the shipping costs depending on all 3 factors in the table rate, so by weight, size and price of product. In the CSV file.
thanks in advance
I would suggest you to get appropriate extension for your need. As you can not make any change or add criteria in default shiping method. Have shared one suggestion below, you can any similar extension.
You can also check out this extension https://amasty.com/shipping-table-rates.html
It will let you use a combination of different attributes to calculate shipping costs. You can create a .csv file with shipping rates and import it.
Hope that helps!