previous iteration in foreach

This will fulfil your requirement if I understood your query correctly

a!localVariables(
  local!data: {
    a!map(
      name: "aaaaa",
      valor: 1
    ),
    a!map(
      name: "bbbbb",
      valor: 10
    ),
    a!map(
      name: "ccccc",
      valor: 10
    ),
    a!map(
      name: "ddddd",
      valor: 10
    ),
    a!map(
      name: "eeeee",
      valor: 45
    )
  },
  local!uniqueValors: union(local!data.valor, tointeger({})),
  local!valorIndices: createdictionary(
    local!uniqueValors,
    enumerate(length(local!uniqueValors))+1
  ),
  a!forEach(
    items: local!data,
    expression: a!map(
      name: fv!item.name,
      pos: property(local!valorIndices, tostring(fv!item.valor), null)
    )
  )
)

The problem with that, and please correct me if I'm wrong, is that it will only work if the 'valor' values are ordered.
In adition, never seen a 'Bean' Appian type as shown in the property function that you are using!!!!!!!!

yes for this the values should be ordered

yes for this the values should be ordered

to use Aryan code, add this as a new variable right after local!data, and use that new variable:

todatasubset(
  arrayToPage: local!data,
  pagingConfiguration: a!pagingInfo(
    startIndex: 1,
    batchSize: -1,
    sort: a!sortInfo(
      field: "valor",
      ascending: true
    )
  )
)

if you see name in the code snippet refresh, edited to "valor".