SQL Server 2019

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DECLARE @x xml = '<People>
    <Person FirstName="Adam"
            LastName="Smith"
            Age="44"
            Weight="178">
        <Texts>
            <Text Country="US"
                  Language="EN"
                  TextType="1">&lt;div&gt;First sentence to retrieve.&lt;/div&gt;</Text>
            <Text Country="GB"
                  Language="EN"
                  TextType="2">&lt;div&gt;Second sentence to retrieve.&lt;/div&gt;</Text>
        </Texts>
    </Person>
</People>
';

SELECT 
    FirstName  = x1.Person.value('@FirstName', 'varchar(100)'),
    LastName   = x1.Person.value('@LastName' , 'varchar(100)'),
    Age        = x1.Person.value('@Age'      , 'int'),
    Weight     = x1.Person.value('@Weight'   , 'decimal(9,5)'),
    Country    = x2.Text.value('@Country' , 'char(2)'),
    [Language] = x2.Text.value('@Language', 'char(2)'),
    TextType   = x2.Text.value('@TextType', 'int'),
    value      = v.InnerXml.value('(div/text())[1]','nvarchar(max)')
FROM @x.nodes('People/Person') x1(Person)
CROSS APPLY x1.Person.nodes('Texts/Text') x2(Text)
CROSS APPLY (VALUES( TRY_CONVERT(xml, x2.Text.value('text()[1]','nvarchar(max)')) )) v(InnerXml);

FirstName	LastName	Age	Weight	Country	Language	TextType	value
Adam	Smith	44	178.00000	US	EN	1	First sentence to retrieve.
Adam	Smith	44	178.00000	GB	EN	2	Second sentence to retrieve.