I would use find to get the folder names, parse them with sed, grep the corresponding id and copy stuff over:

$ find . -mindepth 1 -type d | while read dir; do 
   id=$(echo "$dir" | sed 's/\.\/[[:alpha:]]*\([[:digit:]]*\)_[[:alnum:]]*/\1/'); 
   new_name=$(grep -w "$id" names.csv | cut -d ';' -f 1); 
   mkdir -p "$new_name" && cp -rv "$dir"/* "$new_name"/ && rmdir "$dir"; 
 done

The tricks are

• use mkdir -p which will create the directory and exit silently if it exists.
• use grep -w on the csv file to only get those lines that contain the entire ID bordered by non-word characters. That way you avoid matching both 1123 and 123 for the id 123.

I would use find to get the folder names, parse them with sed, grep the corresponding id and copy stuff over:

$ find . -mindepth 1 -type d | while read dir; do 
   id=$(echo "$dir" | sed 's/\.\/[[:alpha:]]*\([[:digit:]]*\)_[[:alnum:]]*/\1/'); 
   new_name=$(grep -w "$id" names.csv | cut -d ';' -f 1); 
   mkdir -p "$new_name" && mv -rv "$dir"/* "$new_name"/ && rmdir "$dir"; 
 done

The tricks are

• use mkdir -p which will create the directory and exit silently if it exists.
• use grep -w on the csv file to only get those lines that contain the entire ID bordered by non-word characters. That way you avoid matching both 1123 and 123 for the id 123.