If there is a need to access a single VeraCrypt volume simultaneously from multiple operating systems, there are two options:
Advantages: All users can write data to the VeraCrypt volume. The shared volume may be both file-hosted and partition/device-hosted.
Disadvantage: Data sent over the network will not be encrypted. However, it is still possible to encrypt them using e.g. SSL, TLS, VPN, or other technologies.
Remarks: Note that, when you restart the system, the network share will be automatically restored only if the volume is a system favorite volume or an encrypted system partition/drive (for information on how to configure a volume as a system favorite volume, see the chapter System Favorite Volumes).
Advantage: Data sent over the network will be encrypted (however, it is still recommended to encrypt them using e.g. SSL, TLS, VPN, or other appropriate technologies to make traffic analysis more difficult and to preserve the integrity of the data).
Disadvantages: The shared volume may be only file-hosted (not partition/device-hosted). The volume must be mounted in read-only mode under each of the systems (see the section Mount Options for information on how to mount a volume in read-only mode). Note that this requirement applies to unencrypted volumes too. One of the reasons is, for example, the fact that data read from a conventional file system under one OS while the file system is being modified by another OS might be inconsistent (which could result in data corruption).