Multiple headless storefronts without Shopify Plus

[willatex]

I would like to build multiple headless storefronts, however this is only supported by Shopify Plus which is much pricier than the other plans - "basic", "shopify" and "advanced" all support exactly 1 headless storefront.

What are my options here? Do I need to register separate Shopify accounts for each storefront? Can I have multiple subscriptions under a single account?

Does this only apply if I want to use Oxygen? I will be bringing my own frontend - not using hydrogen - effectively I just want to use the storefront api.