All other answers did not work. This is the one that worked:

 sshfs REMOTE_USERNAME@REMOTE_HOST:/remote/dir/path/ local_mnt/ -o umask=022 -o <OTHER_OPTIONS>


This option is important: **umask=022**

Set this to whatever rights you want to provide to the respective local directory/file. Here, 022 means: 755 (777 - 022).
This allows the user and group to read, write and execute the files in the directory, also those that will be created in the future.