No I don't think you can but every month or so in the past Magix does sales promotions where you can buy a given version cheaper. It pays to visit the site every three weeks or so to check the prices. Sometimes Movie Edit Pro Premium is offered at a lower price than the basic Movie Edit Pro.
I may be wrong and you may get an offer that is higher than if you had a more current version. The best way to find out is to see.
I'd say you could. By that I mean that you would get a discounted price for upgrading to MEP 2021 as you have a valid license for an earlier product of same type. Simply put the upgrade offer into the cart and follow the procedure. Payment is the very last step, so you can explore your options without risking paying. If your MEP 2013 product is registered with your (email) account on Magix, ensure you login with same details. If not, you will be asked to provide the serial number of the qualifying product (the product you own that will give you the discount - ie MEP 2013). If Magix does not allow upgrade price from MEP 2013 to MEP 2021, you will be told so.
Whether your projects from MEP 2013 work in MEP 2021 I cannot say, but I think it will - at least to a great extent.
. . . . Whether your projects from MEP 2013 work in MEP 2021 I cannot say, but I think it will - at least to a great extent. . . . .
It is best to finish any ongoing projects before upgrading.
In my experience, the old projects will load correctly after doing some cleaning up of the project folders and the folders where images and video are imported from.
MEP 2021 crashed, due to differences in the temporary files MEP creates, when browsing the folders in the media pane, and complained some files were not readable .
I needed to remove all the following files: .H0, .HDP and mxfilerelatedcache.mxc2 before a project would load correctly.
Do be aware that once the project has been saved from MEP 2021 it does not always load correctly in the version that created it.