Probably it would be wise to discuss whether the tag is useful before continuing with large retagging effort. In fact, many users here are of the opinion that new tags should be discussed on meta before creation.1
The main objection I have to this tag is that it seems to be a bit too specific. After all we already have the tagspropositional-calculus, predicate-logic (and quantifiers), first-order-logic, second-order-logic - some of those will be probably a good fit for most question tagged logic-translation. With only 5 spots for tags available, we might quite easily run out of space.
On the other hand, I understand that the tag encompasses a class of problems which often appears as exercise in various introductory mathematical courses - and thus it might help with searching for examples of such problems.
I would certainly be glad to hear the opinion from other users on this new tag - especially from those who are active in question related to logic, since they are probably in the best position to judge whether this tag might be useful or not.
1See also the older discussion: Should every new tag be discussed on meta before creation? Or a recent comment by Jyrki Lahtonen: "IMHO ideally all new tags at Math.SE should be cleared in meta."