Does Mark to market election under sec 475 for first time for 2019 prevent me from e-filing for 2018?

Can I elect Mark to Market accounting under section 475 for the year 2019 and still be able to e-file 2018 Tax Return?  Or do I have to paper file 2018 tax return?  Please note I was not a full-time trader or had any trading business in 2018.  I am making this election for the first time and that too for year 2019.