What matters is the purposes that the cookies are used for, not how many there are or which service set it. A session cookie that is also used for tracking wou

What matters is the purposes that the cookies are used for, not how many there are or which service set it. A session cookie that is also used for tracking would qualify as both a functional and a tracking cookie, and thus generally be illegal (since you can't consent to the tracking if it's under the threat of being unable to use the service).