您可以使用基本的bash脚本轻松地完成此操作，下面是一个如何完成此操作的示例，并附有解释步骤的注解。

#!/bin/bash

source_dir_a=$1  // Directory containing a files given as first argument
source_dir_b=$2  // Directory containing b files given as second argument

a_files=$(ls $source_dir_a)  // Save list of files in provided a dir

for a_file in $a_files; do   // Loop over the files in the a dir
    echo "a_file=$a_file"
    folder=$(echo $a_file | sed -e 's/^a//g')  // Remove the leading "a" of a files using a regex for the storing folder name
    echo "folder=$folder"
    b_file=$(echo b$folder)  // Adding leading "b" to folder name to have b_file name
    echo "b_file=$b_file"
    mkdir $folder  // Create output folder
    mv $source_dir_a/$a_file $source_dir_b/$b_file $folder // Move the a and b files in output folder
done

缺少的是一些错误检查，特别是当一些预期的文件不存在时。