Lead generation is hard and don't wast your time by doing it wrong
Lead generation have been always one of the challenge at the top of my list when I started to work on building Japan business. It is time consuming process and I can easily wast my time doing something wrong. If you are in charge of building the business in a new market, you want to prove that there is a good product market fit as quick as possible so you can gain more investment into your market.
In a fast pace environment, everyone ask you to show them a result today, but not tomorrow. You will be asked to show them the number of leads, the amount of pipeline, and the money you make. Every week (if not everyday), you get pressures from the management team to tell them how Japan business is doing and when you will have enough leads to hit your monthly target.
While it is necessary to have quick wins to get going, I'd encourage you to take necessary time and effort to build a lead generation engine that will make it possible to grow your business in sustainable manner. Also, I'd suggest you not to wast your time doing something unproductive or unscalable such as cold-calling.
Why I think cold-calling is unproductive or unscalable
When you start to build Japan business, it's likely that you're the only one sales person on the ground and time will be one of the biggest constraint you have. It is said that 1% of people will respond to direct mails in general. And I consider cold-calling is a form of direct mail because I don't see any fundamental difference between DM and cold-calling considering the fact that both of them are push, blind, and brute-force approach. If you can make one call per 5 min and you have 8 hours a day, (unrealistic but in theory) you can make 96 call a day. If you can have 1% of positive reactions to your call, then you will generate 0.96 leads a day. Realistically speaking, I think you can make 50 calls a day at most, then it will be 0.5 leads a day. That is not an encouraging result at all. Moreover, number of leads you'll be generating is proportional to amount of resource you spend that means it won't scale unless you hire more heads. It is not scalable solution, I would say.
What I think where to invest your time
I think you should start to find a champion of your product by meeting existing users of your product. In order to meet with existing users in an efficient manner, I would recommend to hold a meetup with your existing users. Hold a meetup with several short presentation slots where the participants can share their experience with your product. Almost certainly, you will find a champion among the people who gave a presentation at the meetup.
Then, organize a user group of your product and have the champion to lead the group. A initial goal of organizing the user group is to find good user stories from them. People love user stories in Japan and it's pretty effective to gain credibility from the market. When you find good user stories, write and publish the stories through appropriate media outlet. I bet you will see increase on inbound leads after you publish the stories.
When you win new logos, create user stories on why they select your product and how they tackle their issues with your product. Then have them present their stories at the meetup and publish the stories on media outlets. If you iterate this process several rounds, you will see growth on your leads, pipeline, and wins. Instead of wasting your time on unproductive/unscalable activities such as cold calling, invest your time to build a scalable engine that will generate leads in semi-autonomous manner. I think this is something you need to spend time and energy when you enter Japan market.
I had success stories to build and scale lead generation engines like this and painful experience to wast my time on cold-calling. It will take time to see the growth on key metrics with an approach I've suggested, but it will pay off your time and effort in 6 to 8 month.
We provide advisory service on Japan market entry and our focus is to help building scalable engines like this for you. Let's have a chat if you're interested.