ENA minion 2D data doesn't actually have 2D data
Probably not. ENA doesn't have any ability to specifically flag a file as 2D, and the nanopore file formats have changed a lot, so you pretty much need to rely on the submitter to separate out the reads in a meaningful way.

Also, there wasn't really any consistent convention for what ONT used in their read headers. Looking at some of my old files they had a plain sequence ID (i.e. without anything suggesting temp/comp) in different template/complement folders in the FAST5 files for the components of a 2D read and the consensus sequence, but later changed it to _2D_template and _2D_complement as in the example you have (possibly with an intermediate _1D_template and _1D_complement format). Parsing/understanding those FAST5 files can be difficult, which is why poretools was created in the first place.

It's still a bit of a mess, with the 1D$^2$ reads ending up in a Frankenstein-like state that's partially 1D and partially 2D.