If you haven’t found one app for everything you often need to use something more general requiring more setup or learning, or get more specific by building it directly into the theme without apps.
For apps broaden your search to include metafield apps , or personalization apps.
As you’ve found the more specifics you add the less like one niche app will be able to do it all.
Or not able to do it in the way you expect, so the right concept and keywords aren’t used in your search; for example what does “Change dropdown information based on variants” even mean, is that linked-variant options, or for personalization, etc etc.
That’s why this type of combination of requirements is normally done through theme customizations or a combo of 1 app plus customizations to minimize impact to a themes performance. Depending on theme being used for some features possibly already with discussions for DIY theme modifications.
If you want to get this built into you theme without needing monthly apps then contact me directly by mail for services.
Please always provide context, examples: store url, theme name, post url(s) , or any further detail.
Contact Info in signature.
Good Hunting.