The standard macros that come in the fasm download only include imports that are used within the code.

You can use a macro wrapper for "extrn" with the "if used" block to generate symbol entry only if it is actually used by the project.

Could you please show me how to make that "macro wrapper"?

macro extrn def
{
        match ename =as name:size, def
        \{
                if used name
                        extrn ename as name:size
                end if
        \}
}    

macro extrn def
{
        define state 0
        match ename =as name:size, def
        \{
                if used name
                        extrn ename as name:size
                end if
                define state 1
        \}
        match =0 ename =as name, state def
        \{
                if used name
                        extrn ename as name
                end if
                define state 1
        \}
        match =0 name:size, state def
        \{
                if used name
                        extrn name:size
                end if
                define state 1
        \}
        match =0, state
        \{
                if used def
                        extrn def
                end if
        \}
}    

Rebuild the project and it will probably run, but if there is another function that cannot be located, repeat the previous step, that is, search for the function name (both), comment them and rebuild the project.

macro extrn def
{
        define state 0
        match ename =as name:size, def  \{ define state used name \}
        match =0 ename =as name, state def \{ define state used name \}
        match =0 name:size, state def \{ define state used name \}
        if state | used def ; If fasm not parsed second condition in case of truliness first one - this row is workable
                extrn def
        end if
}