Octave can not read .mat file saved by Matlab - matlab

Question

I have a .mat file saved previously using Matlab, and the header says it's v5. When Octave opens it with load(), it complains
warning: load: can not read non-ASCII portions of UTF characters; replacing unreadable characters with '?'
and all the data structure is gone. Dumping out the variable says
scalar structure containing the fields:
where as when loading with Matlab, the structure is clearly shown.
I opened using Scipy, it looks like this
{'__header__': b'MATLAB 5.0 MAT-file, Platform: MACI64, Created on: Sat Aug 4 15:11:49 2018',
'__version__': '1.0',
'__globals__': [],
'doc': <10052x12337 sparse matrix of type '<class 'numpy.float64'>'
with 139589 stored elements in Compressed Sparse Column format>,
'embeddings': array([[ 0.25195 , -1.1312 , -0.016156, ..., -0.024497, -0.4867 ,
-0.42997 ],
[-0.17686 , -0.60787 , 0.29096 , ..., 0.13535 , 0.067657,
0.073915],
[ 0.42054 , 0.39829 , 0.65161 , ..., 0.19725 , 0.58798 ,
-0.04068 ],
...,
[-0.62199 , 0.74258 , -1.0865 , ..., 0.13148 , -1.2473 ,
0.34381 ],
[-0.23951 , 0.15795 , -0.22288 , ..., 0.50322 , -0.27619 ,
0.2259 ],
[-0.21121 , -0.9675 , -0.85478 , ..., -0.59731 , -0.048073,
-0.63362 ]]),
'label_names': array([[array(['business'], dtype='<U8'),
array(['computers'], dtype='<U9'),
array(['culture-arts-entertainment'], dtype='<U26'),
array(['education-science'], dtype='<U17'),
array(['engineering'], dtype='<U11'),
array(['health'], dtype='<U6'),
array(['politics-society'], dtype='<U16'),
array(['sports'], dtype='<U6')]], dtype=object),
'labels': array([[1],
[1],
[1],
...,
[8],
[8],
[8]], dtype=uint8),
'test_idx': array([[ 9868, 9869, 9870, ..., 12335, 12336, 12337]], dtype=uint16),
'train_idx': array([[ 1, 2, 3, ..., 9865, 9866, 9867]], dtype=uint16),
'vocabulary': array([[array(['manufacture'], dtype='<U11'),
array(['manufacturer'], dtype='<U12'),
array(['directory'], dtype='<U9'), ...,
array(['tufts'], dtype='<U5'), array(['reebok'], dtype='<U6'),
array(['chewing'], dtype='<U7')]], dtype=object)}
I tried rewriting the .mat file using different version numbers, and -nocompress option, but none worked.
How can I resave this data structure using Matlab so that Octave can open it without loss of information?