I have 4 variables for a product (size, color, etc..) and the price needs to update once ‘choose size’ variable is selected by the customer. (i have set it up that way, please see screenshot below)
However, the price does not get updated until you choose all of the variables.
Can you kindly verify how it works with default WordPress themes such as TwentyTwenty or WooCommerce Storefront to determine whether it is a problem with our theme or not?
In general, that functionality is related to WooCommerce so as you already understood, the default theme has the same behavior with swatches therefore that issue is not related to the theme. I suggest you contact with WooCommerce support team for further solutions.