There are some patterns to get business manager visa.
It depends on situations, like:
Your business size
Whether you can get support from your friends or relatives in Japan
You already research Japanese market or not
You already have dealing partner or not, etc.
Pattern1
Temporary visitor visa → 4 months business manager visa → Business manager visa
Pattern2
Temporary visitor visa → Business manager visa
Pattern3
4months business manager visa → Business manager visa
Pattern4
(In case you have supporters who can assist your business preparation in Japan)
Business manager visa
Pattern5
(In case you already have other visa in Japan)
Other visa (status change) → Business manager visa
Thank you.