Sakashima of a Thousand Facesutility$15.66It also lets you ignore the legend rule for your permanents, while adding clone-style utility. It is especially strong in commander-focused legendary strategies.
Mishra's Self-ReplicatorutilityBudget$0.29It rewards repetitive board development and can help create multiple copies of itself without caring about the legend rule in the same deckbuilding space. It is narrower, but plays in artifact-centric clone/token shells.
The World Treeutility$6.04It supports legendary-heavy decks by turning all your lands into a mana-fixing engine that helps cast multiple legendary permanents. While it doesn't remove the legend rule, it belongs in the same archetype of legendary-matters support.
Relic of LegendsrampBudget$2.28It specifically rewards legendary permanents and helps generate mana from them, making it a staple in decks that want many legends on board. It does not change the legend rule, but it supports the same deckbuilding theme.
Mirror BoxutilityBudget$4.54This is the closest functional analogue: it ignores the legend rule for your permanents and also boosts legendary creatures you control. It is a strict upgrade in many legendary-heavy decks.
Sakashima the Impostorutility$15.35It can copy a legendary permanent while keeping its own name, allowing multiple legends of the same type to coexist. The effect is narrower than Mirror Gallery, but it serves a similar legend-bending role.
The Flesh Is WeakutilityBudget$0.41It is not a legend-rule card, but it is a cheap board-shaping enchantment/artifact-style hate piece that can be played in similar midrange-control shells. This is a much looser functional match and mainly relevant if you want cheap utility disruption.
Helm of the Hostutility$12.63It creates additional nonlegendary copies of a creature each combat, sidestepping the legend rule by design. It is often used as an alternative in decks that want multiple copies of a key legendary creature.