As the comments already said, Raichu's and Marowak's types and stats are very different, so it's difficult to compare them. However, this is what Smogon has said about Marowak.
Although stiff competition from Pangoro, Golurk, and Heracross makes it niche, Alolan Marowak is an effective wallbreaker for offensive teams due to its combination of extreme power and defensive utility. Alolan Marowak's strong attacks, Thick Club, and offensive typing let it easily force out common slow, bulky Pokemon such as Registeel and Reuniclus, giving it opportunities to fire off powerful attacks or set up Substitute. A useful set of resistances and a great ability in Lightning Rod allow Alolan Marowak to take advantage of Xurkitree to come into play, as well as soft checking other threats like Roserade and Lucario.
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Raichu, on the other hand, has less special attack than Starmie, Raikou, Sigilyph, and Heliolisk, and it also has less speed than Starmie and Raikou. Its lower bulk means it's easy to revenge-kill and can't properly check Togekiss, despite its electric type. Raichu's lack of immunities gives it less chances to switch in and force opponents out, and it can't check ground Pokemon, like Steelix and Rhyperior, as well as other fast psychics can. It has no particularly notable moves or abilities, while your similar options have rapid spin, analytic, magic guard, or reliable healing moves. Given this information, I think Marowak is more likely to be useful than Raichu.
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