It is a division Walshaw is familiar with, having played for Boro, Farsley Celtic, Frickley Athletic and Buxton.
He has played further up the leagues with Darlington AFC in the National League and in National League North with FC Halifax Town, Guiseley, Altrincham, and Harrogate Town.
Walshaw was Ossett's top scorer last season with 12 goals, 11 of which came in the NPL East Division, and ended the season in fine form with six goals in nine games.
After his signing was confirmed, Walshaw said: “I thought it was a great opportunity to play in the league above.
“Having played against Liversedge last season and seeing the project that they’re putting in place and the journey that they’re on, it was pretty much a no-brainer for me really.
“There are some great players at Liversedge. I spoke to Rimmo (Jonathan Rimmington) in depth and he really sold the club.
“Initially from the first point of interest, it appealed to me massively. It’s great to finally be on board.”
He added: “I think I’m a player that brings a good work rate, tenacity, and I have an eye for goal.
“Given the opportunities, I’m confident I can score 20 plus goals.
“The majority of players that Liversedge had last year were set up for the Premier Division. I know they’ve kept a few of the current crop and I’m sure they’ll step up and hold their own at least, and maybe even challenge at the top end of that table.”