Most of the time, yes.
But no, not all of the time.
The QRCode needs to display the JSON output of a mktx call. It looks like this:
{
"complete": false,
"hex": "010000000296f054a6eccd3051444aec20e9c5c9b58739e70c7d958e4eb03587acf99d02e70000000000ffffffffdf350752fe6e27534633bb59327d9feb347756fe8d6e5b0b56312aca57df0eb30000000000ffffffff02f4345c35000000001976a914aaf437e25805f288141bfcdc27887ee5492bd13188ac80969800000000001976a91481acc8b7f9ec7cbf45a02dd8b758c6ac6a1481ca88ac00000000",
"input_info": "[{'scriptPubKey':'76a91411bbdc6e3a27c44644d83f783ca7df3bdc2778e688ac','electrumKeyID':(15,False),'vout':0,'txid':u'e7029df9ac8735b04e8e957d0ce73987b5c9c5e920ec4a445130cdeca654f096'},{'scriptPubKey':'76a914aaf437e25805f288141bfcdc27887ee5492bd13188ac','electrumKeyID':(112,True),'vout':0,'txid':u'b30edf57ca2a31560b5b6e8dfe567734eb9f7d3259bb334653276efe520735df'}]"
}
The type of QRcode that displays transactions supports up to 4296 bytes.
For reference, the above is 751 bytes.
4296 bytes should be enough to display the vast majority of transactions created from a reasonable amount of inputs, but you're right there's still a limitation.
If the QRCode can't be displayed, the user can still save the transaction as a file and move it across with a USB key using the traditional method.
