=COUNTIFS($I$14:$I100;">=2018-1-1";$I$14:$I100;"<=2018-12-31";$H$14:$H100;"Website|Email") works fine here with 6.1.0.2 (given that Options-LibreOffice Calc-Calculate-Enable regular expressions in formulas is enabled - wildcards are the default in Excel types since 5.2). Rather, the $I$14:$I syntax doesn't work here - are you sure it works for you?