Changing job under Designated Activities 46 visa

Is there anyone who has experience with changing jobs under Designated Activities 46 visa (特定活動46号)?
I've been working for a mid-size Japanese company for 2,5 years. The company is a manufacturer, but my job is just n office job in a sales department, including occasional interpreting and marketing. I'm going to transfer to a travel agency, which will probably require me to change visa type to 技人国 visa.
I know that it is required to get a permission for changing jobs when you are on Designated Activities visa.
However,
① is it still required if you change your visa type all together?
② How does the process looks like? Do you have to get this permission first, to be able to apply for a new visa? Or do you just submit it with your basic application?
③ Do you tell your current employee about your job-changing when you submit your request for a permission?
④ Is there a possibility of not receiving a permission, if nothing is wrong with the documents?

Please share your experience. I am stressed as hell not knowing my chances of success, and potentially getting stuck with my company after I already say I'll leave because I didn't receive a permission. That would be awkward 😅

by Aina_Eire