BUR #18969 has been approved by @nonamethanks.
create alias 2ch -> 2channel
create alias 5ch -> 2channel
create alias 5channel -> 2channel
According to Wiki page, the tag for 2channel (2ch) also covers the two sites that were created after the 2014 split, namely 2ch.sg and 5ch.net (also known as 5channel), and even previously linked to the domain of 5ch, but not 2ch.sg for some reason, until now. Despite this, there are no alias or implications for 5ch for the current 2ch tag, despite the tag covers both sites.
So I would like to first rename the current tag (2ch) into the full name of the site (2channel), as the current tag can be easily confused with 2chan aka Futaba channel and 2ch.ru. And the apply the 5channel/5ch alias to the new 2channel tag as an alias.