[Foreigner]

Как-то так, если правильно понял в ПМ:

Код:

@echo off
setlocal enabledelayedexpansion

set "word=пнакрвоулеь"
set "keyw=нквеу"

set "cnt1=99"
set "n=0"

:0
if not "!word:~%n%,1!"=="" (

    set /a cnt1+=1
    set "word_!cnt1!=!word:~%n%,1!"
    set /a n+=1
    goto:0

)

set "cnt2=99"
set "n=0"

:1
if not "!keyw:~%n%,1!"=="" (

    set /a cnt2+=1
    set "keyw_!cnt2!=!keyw:~%n%,1!"
    set /a n+=1
    goto:1

)

:2
for /l %%i in (100,1,%cnt2%) do (

    for /l %%j in (100,1,%cnt1%) do (

        if defined keyw_%%i (

            if "!keyw_%%i!"=="!word_%%j!" (

                set "keyw_%%i="
                set "word_%%j="
                goto:2
            
))))

for /f "tokens=2 delims==" %%i in ('set word_') do 0>nul set /p="%%i"
echo.