I'm using SQLite3 Multiple Ciphers v1.8.2 which I built from its source code. I'm able to create an encrypted database file using this uri: uri=file:encrypt-02.db?mode=rwc&cache=private To specify the encryption mode I use PRAGMAs in this way:

PRAGMA key = 'mypassphrase'
PRAGMA cipher = 'aes256cbc'

Is this the exact order in which you performed the PRAGMA statements?

Everythings works fine, I'm able to create tables and so on ... My problem arise when I want to connect such database in SQLite Studio v3.4.0

If the answer to my above question is yes, it is not surprising that you couldn't open the database in SQLite Studio.

The order of PRAGMA statements matters! If PRAGMA key is executed first the library will use the default cipher scheme - that is, ChaCha20-Poly1305 unless you changed the default when compiling the library.

Executing PRAGMA cipher as the second statement will have no effect.

Am I doing something not allowed?

No. Just change the order of PRAGMA statements on creating the database to

PRAGMA cipher = 'aes256cbc'
PRAGMA key = 'mypassphrase'

Alternatively, you could specify cipher=aes256cbc as an URI parameter.

Should I specify something in "Cipher configuration"?

No, at least not for the cipher scheme aes256cbc.

Thank you @utelle, you are right of course.
My problem was due to PRAGMA execution order, which must be like this

PRAGMA cipher = 'aes256cbc'
PRAGMA key = 'mypassphrase'