Richardson is available on a free transfer after his contract with the National League side expired.
The full-back, 21, was one of the main academy targets this summer as they look to rebuild a side that failed to win a league game last season.
The group has been further weakened by the departures of Bali Mumba and, as it stands, Benji Kimpioka.
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With head of recruitment Ged McNamee back from furlough leave, the club have begun their summer recruitment and recently announced the arrivals of Sam Wilding, Vinnie Steels and Bobby Beaumont.
Richardson is set to be the next, and more will follow.
The club are taking a look at a number of trialists, having faced Consett earlier this week and with more games on the horizon.
One player whose arrival does not look like is Richardson’s former Hartlepool United team-mate Josh Hawkes.
Hawkes was another player on Sunderland’s radar ahead of the summer rebuild but the forward is not expected to join, with Hartlepool United entitled to compensation from his next club after offering improved terms to extend his stay.
The weakness of the U18 and U23 group has been a major source of discontent amongst supporters with the Madrox regime, and non-executive director David Jones said last week it was something the club were working to try and address.
"We're working as hard to bring in targets for the academy as we are for the first team group,” Jones said.
“These U21s now have real bonus value, so if you can get some good young players then you're on the right path.
“It's really tough [to stop players seeking Premier League moves] and it's a challenge that we're really working on.
“I'd be lying if I said that I was happy with the business that's gone on in the last few months and years.
“We've lost some very promising players and that's hugely disappointing.
“It's something we're working on, we've made some changes within the academy and we'll make some more, including appointing a new academy manager.”