Just sort 2 times (and reverse the sort results):
reverse(
sort(
reverse(
sort(
json(
concat(
'[',
'{"Title": "Item 0", "Score": 2001, "RTime": 12},',
'{"Title": "Item 1", "Score": 2000, "RTime": 11},',
'{"Title": "Item 2", "Score": 2001, "RTime": 10},',
'{"Title": "Item 3", "Score": 2000, "RTime": 9},',
'{"Title": "Item 4", "Score": 2001, "RTime": 8},',
'{"Title": "Item 5", "Score": 2000, "RTime": 7},',
'{"Title": "Item 5", "Score": 2001, "RTime": 6}',
']'
)
),
'RTime'
)
),
'Score'
)
)
Result:
[
{
"Title": "Item 5",
"Score": 2001,
"RTime": 6
},
{
"Title": "Item 4",
"Score": 2001,
"RTime": 8
},
{
"Title": "Item 2",
"Score": 2001,
"RTime": 10
},
{
"Title": "Item 0",
"Score": 2001,
"RTime": 12
},
{
"Title": "Item 5",
"Score": 2000,
"RTime": 7
},
{
"Title": "Item 3",
"Score": 2000,
"RTime": 9
},
{
"Title": "Item 1",
"Score": 2000,
"RTime": 11
}
]