Full US ISO's

[MarioMania]

I'm having trouble wording, So

US Library

Can it fit on a 512GB SD Card?

I guess I ask for the Japanese Library too

[Papy.G]

I have found that the nkitted games I happen to have fit for an average 1GB each, see how many of them your library count.(I don't have dual disc games)
Also, found it may be useless to want to get so many games on a big SD (bigger than 128GB), as you'll have to swap memory cards anyways, the file system only allows 128 "files", but allocation system takes one, game hack one, and boot forwarder, one other, it remains 125 for your games, and some of them use more than one file to save various other things that only game progress.
I keep my SD cards and dedicated memory cards in tiny cigarillos tin boxes where they fit perfectly. (Remember that smoking kills)

[N7Kopper]

I have found that the nkitted games I happen to have fit for an average 1GB each, see how many of them your library count.(I don't have dual disc games)
Also, found it may be useless to want to get so many games on a big SD (bigger than 128GB), as you'll have to swap memory cards anyways, the file system only allows 128 "files", but allocation system takes one, game hack one, and boot forwarder, one other, it remains 125 for your games, and some of them use more than one file to save various other things that only game progress.
I keep my SD cards and dedicated memory cards in tiny cigarillos tin boxes where they fit perfectly. (Remember that smoking kills)

You could get a MemcardPRO as a solution to this, if I recall. Multiple memory card images on a single physical device, combined with nKit trims can do wonders.

Although if you're serious about this, check to see if certain games have superior PAL versions. I know that Little King's Story for Wii has a superior NA version that came out later. Got burned by that fact.