Requested feature overview description.
When someone attempts to create a new tag alias, the tag alias page should check the "Reason" box for phrases like "same artist" and "same person". If any of those phrases are found, it should refuse to let the new alias be submitted, until the user adds at least one or two off-site links to the "Reason" box.
Why would it be useful?
A lot of people seem to post "same artist" alias requests without linking to any profiles of the artist in question. This causes e621 staff or other users to dig around on FA, Twitter, Internet Archive, etc, to confirm that the names given are actually the same person. This change would put the burden of proof on the alias proposer, rather than the staff.
Possible drawbacks:
If you force the alias proposer to include an offsite link before the proposal is accepted, they might just fill in https://google.com/ or similar to pass the check.
Automated parsing of natural language is always tough. Collecting all the phrases to look for may take a while. Also, people might try things like "sam3 art1st" to fool the parsing and bypass the link requirement.
What part(s) of the site page(s) are affected?
The new tag alias page.