Sigma-9
These Sigma-9 styled interwikis use the version of Sigma-9 with added interwiki selectors (https://github.com/scpwiki/sigma9/pull/42).
SCP listing for "main" from perspective of SCP EN
SCP listing for "scp-6000" from perspective of SCP CN
WL listing for "start" from perspective of WL EN
SCP listing for "nodngufiapgnufiapgnrjiagnrnjgiw" from perspective of SCP EN
It is not possible to have multiple interwikis on the same page with different styles, so examples of interwikis with other styles have been extracted to different pages.
BHL
Demo for BHL styling: http://scp-sandbox-3.wikidot.com/interwiki-bhl
Note that a cached copy of interwiki-customised CSS from the current CN interwiki is being used here, as BHL does not at the time of writing natively support the new interwiki
Inkblot
Demo for Inkblot, a Sigma-9 theme: http://scp-sandbox-3.wikidot.com/interwiki-inkblot
This uses the CSS from the main Inkblot theme from SCP EN, which already natively supports the new interwiki