Did the error with setuptool disappeared, at least ?
I don’t know but why not trying the touch of METADATA
Just in case I give you the content of this file on my server :
/opt/yunohost/matrix-synapse/lib/python3.9/site-packages/cffi-1.15.1.dist-info # cat METADATA
Metadata-Version: 2.1
Name: cffi
Version: 1.15.1
Summary: Foreign Function Interface for Python calling C code.
Home-page: http://cffi.readthedocs.org
Author: Armin Rigo, Maciej Fijalkowski
Author-email: python-cffi@googlegroups.com
License: MIT
Classifier: Programming Language :: Python
Classifier: Programming Language :: Python :: 2
Classifier: Programming Language :: Python :: 2.7
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.6
Classifier: Programming Language :: Python :: 3.7
Classifier: Programming Language :: Python :: 3.8
Classifier: Programming Language :: Python :: 3.9
Classifier: Programming Language :: Python :: 3.10
Classifier: Programming Language :: Python :: Implementation :: CPython
Classifier: Programming Language :: Python :: Implementation :: PyPy
Classifier: License :: OSI Approved :: MIT License
License-File: LICENSE
Requires-Dist: pycparser
CFFI
====
Foreign Function Interface for Python calling C code.
Please see the `Documentation <http://cffi.readthedocs.org/>`_.
Contact
-------
`Mailing list <https://groups.google.com/forum/#!forum/python-cffi>`_
There are some other files in this folder :
/opt/yunohost/matrix-synapse/lib/python3.9/site-packages/cffi-1.15.1.dist-info # ls -al
total 44
drwxr-xr-x 2 matrix-synapse root 4096 Sep 27 2022 .
drwxrwxrwx 138 matrix-synapse root 12288 Sep 21 18:06 ..
-rw-r--r-- 1 matrix-synapse root 75 Sep 27 2022 entry_points.txt
-rw-r--r-- 1 matrix-synapse root 4 Sep 27 2022 INSTALLER
-rw-r--r-- 1 matrix-synapse root 1294 Sep 27 2022 LICENSE
-rw-r--r-- 1 matrix-synapse root 1144 Sep 27 2022 METADATA
-rw-r--r-- 1 matrix-synapse root 2992 Sep 27 2022 RECORD
-rw-r--r-- 1 matrix-synapse root 19 Sep 27 2022 top_level.txt
-rw-r--r-- 1 matrix-synapse root 150 Sep 27 2022 WHEEL
/opt/yunohost/matrix-synapse/lib/python3.9/site-packages/cffi-1.15.1.dist-info # cat entry_points.txt
[distutils.setup_keywords]
cffi_modules = cffi.setuptools_ext:cffi_modules
/opt/yunohost/matrix-synapse/lib/python3.9/site-packages/cffi-1.15.1.dist-info # cat INSTALLER
pip
/opt/yunohost/matrix-synapse/lib/python3.9/site-packages/cffi-1.15.1.dist-info # cat RECORD
_cffi_backend.cpython-39-aarch64-linux-gnu.so,sha256=mYh4Dy89jojXJX-ab6fqsIjPaYOXIpOKMDkU4DGdzBE,1052976
cffi-1.15.1.dist-info/INSTALLER,sha256=zuuue4knoyJ-UwPPXg8fezS7VCrXJQrAP7zeNuwvFQg,4
cffi-1.15.1.dist-info/LICENSE,sha256=BLgPWwd7vtaICM_rreteNSPyqMmpZJXFh72W3x6sKjM,1294
cffi-1.15.1.dist-info/METADATA,sha256=KP4G3WmavRgDGwD2b8Y_eDsM1YeV6ckcG6Alz3-D8VY,1144
cffi-1.15.1.dist-info/RECORD,,
cffi-1.15.1.dist-info/WHEEL,sha256=EFW0IeA9Np1ksorViC508uzcNuLwTraoZLYyYhhpIFI,150
cffi-1.15.1.dist-info/entry_points.txt,sha256=y6jTxnyeuLnL-XJcDv8uML3n6wyYiGRg8MTp_QGJ9Ho,75
cffi-1.15.1.dist-info/top_level.txt,sha256=rE7WR3rZfNKxWI9-jn6hsHCAl7MDkB-FmuQbxWjFehQ,19
cffi.libs/libffi-2a6f5b63.so.8.1.0,sha256=uFcmlDsVhvOzDnZnzRz8x20BiBv18IwLJOzwwnc9-Ko,198248
cffi/__init__.py,sha256=6xB_tafGvhhM5Xvj0Ova3oPC2SEhVlLTEObVLnazeiM,513
cffi/__pycache__/__init__.cpython-39.pyc,,
cffi/__pycache__/api.cpython-39.pyc,,
cffi/__pycache__/backend_ctypes.cpython-39.pyc,,
cffi/__pycache__/cffi_opcode.cpython-39.pyc,,
cffi/__pycache__/commontypes.cpython-39.pyc,,
cffi/__pycache__/cparser.cpython-39.pyc,,
cffi/__pycache__/error.cpython-39.pyc,,
cffi/__pycache__/ffiplatform.cpython-39.pyc,,
cffi/__pycache__/lock.cpython-39.pyc,,
cffi/__pycache__/model.cpython-39.pyc,,
cffi/__pycache__/pkgconfig.cpython-39.pyc,,
cffi/__pycache__/recompiler.cpython-39.pyc,,
cffi/__pycache__/setuptools_ext.cpython-39.pyc,,
cffi/__pycache__/vengine_cpy.cpython-39.pyc,,
cffi/__pycache__/vengine_gen.cpython-39.pyc,,
cffi/__pycache__/verifier.cpython-39.pyc,,
cffi/_cffi_errors.h,sha256=zQXt7uR_m8gUW-fI2hJg0KoSkJFwXv8RGUkEDZ177dQ,3908
cffi/_cffi_include.h,sha256=tKnA1rdSoPHp23FnDL1mDGwFo-Uj6fXfA6vA6kcoEUc,14800
cffi/_embedding.h,sha256=9tnjF44QRobR8z0FGqAmAZY-wMSBOae1SUPqHccowqc,17680
cffi/api.py,sha256=yxJalIePbr1mz_WxAHokSwyP5CVYde44m-nolHnbJNo,42064
cffi/backend_ctypes.py,sha256=h5ZIzLc6BFVXnGyc9xPqZWUS7qGy7yFSDqXe68Sa8z4,42454
cffi/cffi_opcode.py,sha256=v9RdD_ovA8rCtqsC95Ivki5V667rAOhGgs3fb2q9xpM,5724
cffi/commontypes.py,sha256=QS4uxCDI7JhtTyjh1hlnCA-gynmaszWxJaRRLGkJa1A,2689
cffi/cparser.py,sha256=rO_1pELRw1gI1DE1m4gi2ik5JMfpxouAACLXpRPlVEA,44231
cffi/error.py,sha256=v6xTiS4U0kvDcy4h_BDRo5v39ZQuj-IMRYLv5ETddZs,877
cffi/ffiplatform.py,sha256=HMXqR8ks2wtdsNxGaWpQ_PyqIvtiuos_vf1qKCy-cwg,4046
cffi/lock.py,sha256=l9TTdwMIMpi6jDkJGnQgE9cvTIR7CAntIJr8EGHt3pY,747
cffi/model.py,sha256=_GH_UF1Rn9vC4AvmgJm6qj7RUXXG3eqKPc8bPxxyBKE,21768
cffi/parse_c_type.h,sha256=OdwQfwM9ktq6vlCB43exFQmxDBtj2MBNdK8LYl15tjw,5976
cffi/pkgconfig.py,sha256=LP1w7vmWvmKwyqLaU1Z243FOWGNQMrgMUZrvgFuOlco,4374
cffi/recompiler.py,sha256=YgVYTh2CrXIobo-vMk7_K9mwAXdd_LqB4-IbYABQ488,64598
cffi/setuptools_ext.py,sha256=RUR17N5f8gpiQBBlXL34P9FtOu1mhHIaAf3WJlg5S4I,8931
cffi/vengine_cpy.py,sha256=YglN8YS-UaHEv2k2cxgotNWE87dHX20-68EyKoiKUYA,43320
cffi/vengine_gen.py,sha256=5dX7s1DU6pTBOMI6oTVn_8Bnmru_lj932B6b4v29Hlg,26684
cffi/verifier.py,sha256=ESwuXWXtXrKEagCKveLRDjFzLNCyaKdqAgAlKREcyhY,11253
/opt/yunohost/matrix-synapse/lib/python3.9/site-packages/cffi-1.15.1.dist-info # cat top_level.txt
_cffi_backend
cffi
This one look specific to the architecture (here ARM64)
/opt/yunohost/matrix-synapse/lib/python3.9/site-packages/cffi-1.15.1.dist-info # cat WHEEL
Wheel-Version: 1.0
Generator: bdist_wheel (0.37.1)
Root-Is-Purelib: false
Tag: cp39-cp39-manylinux_2_17_aarch64
Tag: cp39-cp39-manylinux2014_aarch64