Classic Commerce Github issue 131 discusses the problem where some WooCommerce extensions won’t activate unless they detect that WooCommerce is installed and active.
A filter was proposed to fool the extensions into thinking WC was active, but unfortunately it doesn’t work.
However, an empty placeholder plugin structured as woocommerce/woocommerce.php does work.
I created one and it enabled me to use the Wirecard payment gateway extension, which wouldn’t work when it didn’t believe WC was present and active. I had to set the version to a high number to stop ClassicPress trying to find updates for it on the WP repo. I set it to version 9999.0.
I can’t attach zips here but I attached it to a comment on the Github issue.