Steps to reproduce the issue

Install 4.0-dev. Install some languages. Install the multilingual sample data.

Bug

500 'v40_multi.wa.state_id' isn't in GROUP BY
articles Manager
0 Argument 1 passed to Joomla\Utilities\ArrayHelpergetColumn() must be of the type array, boolean given, called in /administrator/components/com_content/Model/ArticlesModel.php on line 483

basic solution proposed by @rdeutz

in ArticlesModel line 286ff (I love the $bingo variable ? )

		// Join over the associations.
		if (Associations::isEnabled())
		{
			$bingo = $associationsGroupBy;
   			$bingo[] = 'wa.state_id';
   			$bingo[] = 'ws.title';
   			$bingo[] = 'ws.condition';
   			$bingo[] = 'ws.workflow_id';
			
			$query->select('COUNT(asso2.id)>1 as association')
				->join('LEFT', '#__associations AS asso ON asso.id = a.id AND asso.context=' . $db->quote('com_content.item'))
				->join('LEFT', '#__associations AS asso2 ON asso2.key = asso.key')
				->group($db->quoteName($bingo));
		}

It works here.

Additional comments

I do not understand the new Table Options: Select State and Select Condition.

@bembelimen