The speaker makes use of possessive pronouns such as "my" to show that he has ownership of the Duchess, and shows that she is a possession not an individual
The statue is the last thing he shows the envoy, and this could be seen as a warning that he expects his next wife to be tamed, seeing as he was successful in taming his last Duchess
Both the poets - Keats and Browning - choose to display a negative view of love with a focus on a one sided relationship, with the imbalanced power dynamic appearing to cause serious issues in the poem's respective relationships
In Browning's poem, the Duchess is powerless - doesn't have a name and has imagery associated with her which makes her seem innocent. In Keats' poem, the Knight is similarly depicted as powerless - for example, the adjective "alone" is repeated
Whereas the depiction of the Duchess and the Duke in 'Last Duchess' is a typical portrayal of patriarchal power, the depiction of the Knight in Keats' work is abnormal because the female creature is shown to be overpowering the Knight