They offer options to access the site in different languages or countries, while their contents and services are essentially the same

They present not only different languages, but also different contents and even different services in each language and country

Multivariate testing

Split URL testing

A/B testing

Conversion rate testing

No

Sometimes

Yes

Paid search

Organic search

In small and large companies projects, more emphasis is placed on laying the foundations for SEO, while in startup projects the focus is placed on demonstrating a return on their investments 

In startup projects, more emphasis is placed on laying the foundations for SEO, while in projects for small and large companies the focus is placed on demonstrating a return on their investments 

Through VPNs

Changing the Region settings in the Advanced Search of the search engine

Using a browser with the language set to the language used in the project

Querying the search engine in the language used in the project

Through a browser window in incognito mode

Hybrid

Manual

Automatic

SEM/PPC/Paid Search

SEO

All the other options are incorrect

Working on Paid Search usually requires a larger team than working on SEO

Paid Search and SEO are best used toghether when trying to position URL in highly competed SERPs

SEO usually works best for positioning URLs with informational search intent

Yes, it makes sense to compare them on a specific date because they give you a more complete picture of the affinity observed in the link profile.

It does not make much sense to compare them with each other, although it does make sense to see the evolution of each of them over time for a given project.

No, it does not make any sense, since they are proprietary metrics, each of them is obtained from a different methodology.