Have you seen the instructions attached to the first post in this thread
? That gives the steps you need to create a Kobo dictionary, all of which can be automated. There are three main steps:
1. Converting the source dictionary into the html format used by the Kobo.
2. Creating an index from the html.
3. Packaging the html and index into the Kobo dictionary.
Steps 2 & 3 are generic and are good candidates for a generic program; in fact I have code that does this already. I'm thinking about tidying it up and making it generally available; I don't know if there is much demand for it. It is Windows only.
Step 1 is the most time consuming and is bespoke to each source dictionary, as they all have their own formats. Again for this step I write a program, but it is specific to each source dictionary. Depending on the source, it can be done manually using a text editor and e.g., regular expressions, or perhaps xslt tranformations if you have the skill.
I think AlPe is also working on a converter program; see here