Miraheze provides imports for all wikis. To request an import please go to Special:RequestImportDump and fill in the form. You can read Moving a wiki to Miraheze if you need help creating a dump file.
If you wish to also import images, please create a Phabricator task and use a cloud provider (like e.g. Google Drive or Dropbox) to link us to your images. If it is a private wiki you can send this by email to sremiraheze.org.