GEDmatch triangulation matching works from names. Only FTDNA provides email info in their files. From a practical standpoint, the GEDmatch triangulation routine does not work well with 'cross company' results, because names are often slightly different between the 2 companies. I'm OK with supporting an 'unofficial' format if it contains the necessary info. It needs names of the 2 people who match, largest segment (in cM) and total match (in cM). If Ancestry doesn't provide cM, I can derive those from chromosome plus start/stop position information of the matching segments.

GEDmatch also has a somewhat similar utility that's listed as "People who match one kit, but not the other". In reality, it also gives "People who match both kits" which is essentially what the triangulation utility does - except this one works from uploaded DNA - and it works today (if you've finished batch processing).