Can I port this plu­g­in to an­oth­er CMS?

Yes. In fact, We have done most of the work for you. I have sep­a­rat­ed all of the core func­tion­al­i­ty of wp-​Typography in­to a stand-​alone project—PHP Ty­pog­ra­phy—that is eas­i­ly port­ed to any oth­er PHP based con­tent man­age­ment sys­tem. There is even de­tailed doc­u­men­ta­tion of the PHP Ty­pog­ra­phy func­tion­al­i­ty.