In State Machine diagrams, in some online resources, the condition is merely drawn on the arrow (the left figure below) and in others similar to right figure, where a choice node is specifically used.
Which one of the following is correct UML?
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As there are no triggers defined for the transitions, only guards, they are completion transitions, meaning that once a state finishes its actions, a completion event will be generated to leave the source state if a valid transition can be found.
As you frame the question "Using Choice Node...", the diamond represents a dynamic conditional branch, meaning that the guards of the outbound transitions will only be checked after the transition in.
Therefore, in the case where Value equals 8, the version on the right would result in an invalid state, as you would leave State A on completion, entering the choice pseudo state, but not be able to enter either State B or State C as neither guard evaluate true. Whereas the version on the left would not leave State A.
So to answer your question, they are both "correct UML", but they are not equivalent.
See "126.96.36.199.3 Completion Transitions and completion events" in https://www.omg.org/spec/UML/2.5.1/PDF most of what you need for this question is there.