Hi @MMpaquette !
Our suggestion is that you included yourself as a recipient on the 400 envelopes you send (so you will need to sign 400 times).
This is our recommendation, because this is the only way will you appear as a (completed) recipient in the Certificate of Completion for each envelope.
If you use a file with your signature included before the Docusign signing cerimony, your name will not appear as a part of the envelope, nor will it appear in the envelope history as the recipient of each envelope.
However, if this procedure will be common, I would recommend that you contact the Docusign Sales team to check any possibilities for developing integration for your scenario.