Depth versus practicality
Listrak has more retail depth. Omnisend is more practical for many stores.
That does not make one universally better. It means the right choice depends on whether your team needs an enterprise retail partner or a tool it can start using quickly.
Where Listrak wins
Listrak wins when the ecommerce program is mature enough to use deeper recommendations, SMS, behavioral triggers, and vendor support.
Where Omnisend wins
Omnisend wins when you want email, SMS, push, and forms in one approachable platform. It is a better fit for stores that need more than Shopify Email but less than an enterprise suite.
Where Sequenzy fits
Sequenzy fits when email is the whole job. If you are not ready to use SMS or push, start with email automation that is easier to launch.