The stadium will be built next to a Tesco superstore
Opponents of plans for the new Everton and Tesco development in Kirkby are calling on neighbouring councils to help their cause.
Consultants employed by Liverpool City Council backed some residents' fears that Kirkby, which is in Knowsley, could be too small for development.
But a planning report calling on the council to object to the plans was withdrawn after changes to the scheme.
Campaigners hope Merseyside councils may still formally object.
Although previously supportive of the Kirkby regeneration, councillors in Liverpool were recommended to formally object based on observations by planning consultants.
A report said that Tesco had "not adequately demonstrated a need" for the huge size of the proposed store.
It also said the scale of the project was "not appropriate to the role and function" of Kirkby town centre, and underestimated the amount of trade that would be drawn away from Liverpool.
However, Knowsley Council has informed the council of "significant changes" to the £400m regeneration scheme.
"While we are clarifying those changes the item was withdrawn and we will consider our position when we see what these changes are," a city council spokesman said.
The neighbouring borough authority is expected to decide on the 85,500 sq m development and 50,000 seat stadium at the end of May.
Ian Morris, of the Kirkby Residents Action Group, said: "I would welcome objections from Liverpool City Council and other surrounding councils to stop the size of the redevelopment that is being proposed.
"They are proposing to build the biggest Tesco store in the country alongside a 55,000 [seat] football stadium for Everton.
"Kirkby is too small for the stadium and for the retail development of the size they are actually proposing."
A spokesman for Tesco said the plans had been altered in line with concerns previously raised and was now "a product of Tesco, Everton and the residents themselves".
"We've now got a scheme that followed a wide-ranging consultation that has been well-received by the people of Kirkby.
"This is about enabling more investment into Kirkby and it needs to be a certain scale to make that happen.
"The reaction from the vast majority has been to grasp this opportunity and go a for a large-scale redevelopment of the town and when you get out on to streets you find people are in support."