Proper JSON construction to add different languages - postgresql

Question

I need to change this Query to be able to handle the different languages.
I'm already on my way but I want to be able to write out languages also.
with data (code, bez) as (
values
('01', 'Test 1'),
('02', 'Test 2'),
('03', 'Test 3'),
('04', 'Test 4')
), languages (lang) as (
values ('de'), ('fr'), ('it'), ('en')
)
select jsonb_build_object('cus_test', jsonb_object_agg('1'||code, l))
from (
select code,
jsonb_object_agg('bezeichnung_'||lang, bez) ||
jsonb_build_object('code', '1'||code) ||
jsonb_build_object('cus_immopaccode', code) ||
jsonb_build_object('cus_immopac_mandant_cd', 1) as l
from data
cross join languages
group by data.code
) x
;
At the moment the output is like this:
{
"cus_test": {
"101": {
"code": "101",
"bezeichnung_de": "Test 1",
"bezeichnung_en": "Test 1",
"bezeichnung_fr": "Test 1",
"bezeichnung_it": "Test 1",
"cus_immopaccode": "01",
"cus_immopac_mandant_cd": 1
},
"102": {
"code": "102",
"bezeichnung_de": "Test 2",
"bezeichnung_en": "Test 2",
"bezeichnung_fr": "Test 2",
"bezeichnung_it": "Test 2",
"cus_immopaccode": "02",
"cus_immopac_mandant_cd": 1
},
"103": {
"code": "103",
"bezeichnung_de": "Test 3",
"bezeichnung_en": "Test 3",
"bezeichnung_fr": "Test 3",
"bezeichnung_it": "Test 3",
"cus_immopaccode": "03",
"cus_immopac_mandant_cd": 1
},
"104": {
"code": "104",
"bezeichnung_de": "Test 4",
"bezeichnung_en": "Test 4",
"bezeichnung_fr": "Test 4",
"bezeichnung_it": "Test 4",
"cus_immopaccode": "04",
"cus_immopac_mandant_cd": 1
}
}
}
Now I want to add the language translations to it like this:
with data (code, bez_de, bez_fr, bez_it, bez_en) as (
values
('01','Pruefung 1', 'Test 1','la proova 1','Test 1'),
('02', 'Pruefung 1', 'Test 1','la proova 1','Test 1'),
('03', 'Pruefung 1', 'Test 1','la proova 1','Test 1'),
('04', 'Pruefung 1', 'Test 1','la proova 1','Test 1'))
But I don't how to implement it correctly.