batch Find and Replace for docx files

Maybe http://gregmaxey.mvps.org/word_tip_pages/vba_find_and_replace.html would help? If not, you can roll your own with a macro and a table

Create a document with a two column table. Enter the words you want to find in the first column and the formatted versions you wish to replace then with in the second column.  Save the file and put the filename and path where indicated.

Sub ReplaceFromTableList()
Dim oChanges As Document, oDoc As Document
Dim oTable As Table
Dim oRng As Range
Dim rFindText As Range, rReplacement As Range
Dim i As Long
Dim sFname As String
Dim sAsk As String
    sFname = "D:\My Documents\Test\Changes.docx"
    Set oDoc = ActiveDocument
    Set oChanges = Documents.Open(Filename:=sFname, Visible:=False)
    Set oTable = oChanges.Tables(1)
    For i = 1 To oTable.Rows.Count
        Set oRng = oDoc.Range
        Set rFindText = oTable.Cell(i, 1).Range
        rFindText.End = rFindText.End - 1
        Set rReplacement = oTable.Cell(i, 2).Range
        rReplacement.End = rReplacement.End - 1
        With oRng.Find
            .ClearFormatting
            .Replacement.ClearFormatting
            Do While .Execute(findText:=rFindText, _
                              MatchWholeWord:=True, _
                              MatchWildcards:=False, _
                              Forward:=True, _
                              Wrap:=wdFindStop) = True
                oRng.Select
                sAsk = MsgBox("Replace - " & vbCr & oRng & vbCr + vbCr & _
                              "with - " & vbCr & rReplacement, vbYesNo, _
                              "Replace from Table")

                If sAsk = vbYes Then
                    oRng.FormattedText = rReplacement.FormattedText
                End If
                oRng.Collapse wdCollapseEnd
            Loop
        End With
    Next i
    oChanges.Close wdDoNotSaveChanges
End Sub