Create a plain text .htaccess file (where the olddomain.com is located) or if you have add the lines from the example to the top of your existing .htaccess file.
# Enable mod_rewrite
RewriteEngine On
# Redirect matching requests to new domain
RewriteRule ^index.php/journal-1(.*)$ http://www.newdomain-1.com/journal-1$1 [L,R=301]
RewriteRule ^index.php/journal-2(.*)$ http://www.newdomain-2.com/journal-2$1 [L,R=301]
To avoid duplicate content and indexing issues, can I delete the old OJS installation? Is it possible to redirect the users who are trying to access the content (from old domain) to new domain.
Could you kindly provide me with further details about what you are trying to achieve? I am having difficulty comprehending your request and would appreciate it if you could clarify your intentions.