Please demonstrait how you have setup?
I think you might strugle to have dynamic order tags based on other order tags…
You might need to automate some of the options rather than use tags to achive what your looking to do.
An example would be an order tag added/updated rule with constraint of tag group = shoes with an ask question to add the second option/tag, for size maybe an update/tag order action using [?Prompt] for the tag name to display a keyboard/numberpad to enter the size.