That's from the Chartworld shop, isn't it?
S-63: official format which can be used in all navigation systems which are able to read ENCs
directENC: a format (SENC) which makes handling and loading charts much easier. Please contact the navigation system manufacturer or ChartWorld to have confirmed that such format is supported.
What they call directENC is their special SENC or private "precooked" format.
we have an equivalent own SENC. Here and in the case of S-63 this is called eSENC (encrypted SENC).
So you need to license
the S-63 ENC charts and not the directENCs in order to use them with OpenCPN