To fix internet access for Kodi on Batocera.linux there is a very simple thing to do !

Go to your Settings/Services -> SMB client

And change its two parameters

Minimum protocol version :
Maximum protocol version :

By

Minimum protocol version : SMBv2
Maximum protocol version : SMBv3

Minimum protocol version

Set the minimum SMB protocol version to negotiate when making connections. Forcing SMBv2 may be required to prevent SMBv1 use on some OS. Please be aware, that we do not recommend to use SMBv1 at all for security reasons as it's known vulnarable. So please enable SMBv1 only if you know what you are doing.

Maximum protocol version

Set the maximum SMBB protocol version to negotiate when making connections. Forcing SMBv2 or SMBv1 compatibility may be required with older NAS and Windows shares. Please make sure if the SMB server you want to connect to supports at least SMBv2 and do required changes on the server side (and also for the shares) before enabling SMBv1.

Source : https://kodi.wiki/view/Settings/Services/SMB_Client#Minimum_protocol_version