At the moment, we do not support for using Transcy app for all development store, affiliate store, partner test store or users who still being within trial of Shopify plan.
Sorry for this inconvenience.
But once you're in paid Shopify plan officially, you could feel free to install and choose any favorite plan in Transcy app.
For further information about all our pricing plans, please visit here.
Hope this would be helpful for you.
Should you need further support, please feel free to contact us via live chat or email us at firstname.lastname@example.org