Google's John Mueller, I think - I am not 100% sure - hinted that reports for signed exchanges may be coming at some point in the future to Google Search Console. This is in addition to signed exchanges being currently supported in the AMP report.
John Mueller said at the 38:16 mark into this past Friday's Google hangout that "over time, as we see more sites implement this [signed exchanges] then we will be able to figure out what the right balance is over there [crawling/indexing] and maybe even have tools that give you some insight into what is actually happening there."
The "give you some insight into what is actually happening there" I think means reporting within Google Search Console.
The question that was asked started at about 35 minutes into that video where the question was if signed exchanges can improve core web vitals? In short, it would be taken into account because Google uses Chrome user experience data, real user data.
Here is the video embed:
Signed HTTP Exchange (or "SXG") is a subset of the emerging technology called Web Packages, which enables publishers to safely make their content portable, i.e. available for redistribution by other parties, while still keeping the content’s integrity and attribution. Portable content has many benefits, from enabling faster content delivery to facilitating content sharing between users, and simpler offline experiences.
Forum discussion at the YouTube Community.
This post was pre-written and scheduled to be automatically posted today, I am offline for a holiday and unable to respond to comments or questions until late Tuesday night.