What you describe should be doable. I don’t think that falls under the initial question of will it “just work” however.
I think it would still “just work”; there just may be functionality like the ec that may not have been upstreamed to debian 10; which you may need to get from elsewhere (could check backports/testing/sid). You can also use apt preferences to get only the specific packages you want from outside debian 10 instead of making a franken os.