You should update a Woocommerce Payment Gateway to allow admin-updates (see: https://docs.woocommerce.com/document/subscriptions/develop/payment-gateway-integration/change-payment-method-admin/)
It's a SEPA-Payment-Gateway for Europe and it's already coded - but I'm missing some features:
- allow editing by admin
- allow creating orders by admin with this payment gateway
- allow importing
Of course I will provide the source code, you should validate it yourself with Woocommerce, WC Subscriptions and the Woocommerce Subscriptions updater (https://github.com/Prospress/woocommerce-subscriptions-importer-exporter).
It's not a big deal, but I'm looking forward in further assignments. My company is located in Germany, English or German required, VAT-ID (EU) desired.