Replying to what xxmai posted, what I meant by fan translations is exactly what you're describing in that post. You're a fan, not staff of the international sales agent, and you're translating the role yourself by looking it up in dictionaries.
However, the literal, direct, standard translation of a word used as movie/TV credit is rarely the same as its English equivalent in the context of it being used as a movie/TV credit.
A famous example in another language combination is the French term producteur exécutif, which is the French equivalent of "Line Producer" or "Executive in Charge of Production". It is not the equivalent of what it literally means (and is frequently mistranslated as), "Executive Producer". Producteur délégué is the French equivalent of Executive Producer.
A frequent bugbear for me is that the Japanese credit 美術監督 literally translates as "Art Director", but on a live-action production it's closer to "Production Designer" (with just 美術 being the equivalent of Art Director, as I went through before). In anime, it means the person in charge the backgrounds, which on English-language productions is called 'Background Supervisor" or similar. This is very different from an "Art Director" in English-language animation, which is someone who supervises the whole look of a production, including characters and colours as well as backgrounds.
So looking up the literal meaning of a credit in a dictionary can be used as a last resort, but it should not be used if there are other options available.
Looking up what is used in official credit translations on official English-language posters, in press kits and in on-screen credits is a much better way of going about it, as is looking to see if awarding bodies with a prize for it give an English name for it.
But even official translations can misunderstand things (as in all the official translation of anime credits that translate 美術監督 as "Art Director"). So those can be factors in the decision, but, in order to make the right one (instead of further propagating a misunderstanding), another factor needs to be understanding what the East Asian credit actually entails, and what English credits in the same field entail.
As I give an example of, 企画 can also be translated officially in press kits as "Development", so that needs considering as a possibility for that reason. I'm not saying that "Planning" is wrong; unlike in the examples I gave above, there's no English role with that name for it to conflict with. Just giving some input as to why it might not be the best English word to use. And I can see the logic of how the choice of "Planning" would emphasise the specificity of the role to East Asian production processes, rather than its similarity to a developer on an English-language production.
It also needs some thought (based on what how the other roles on MDL are named, and how the role tends to be written in official English-language credits) given to whether it should formatted as "Planning", "Planner" or "Planned by", or "Development", "Developer", or "Developed by".