Sc-im is spreadsheet software that can view xlsx, csv, and its own native sc files.
It has vim-like keys and can transform spreadsheet file formats between each other.
Start SC-IM:
$ scim path/to/file.csv
Enter a string into the current cell:
<|>
Enter a numeric constant into the current cell:
=
Edit string in the current cell:
E
Edit number in the current cell:
e
Center align the current cell:
|