I won't waste your time with a long intro, here's how to bulk import links.
Within a column, click on the three dots followed by 'Import & Export'
You can now add one or multiple links
You can a-sign a name to the card as well by adding "| Card name"
Named: https://producthunt.com | Product Hunt
You can now import your links from OneTab in just a few clicks:
Visit One tab > Export
And use the above popup to import your data.
NEW: You can now bulk edit bookmarks as well. Here is how: