Do you know of the international speech and leadership club Toastmasters? They have chapters all over the world, with many in Japan. Most people that join these clubs are interested in international exchange and speak English. It is great for a person new to Japan or someone that wants to expand their professional network. I was hooked when I joined a bilingual club (English and Japanese) in my area. You can search to see if there is a club near you on the website: https://www.toastmasters.org/
About 10 minutes walk from Haijima Station, there is a congregation that welcomes anyone interested to join the religious organization, Church of Christ. Their activities are not just limited to worship services, but also includes picnic and Sakura Viewing as acquaintance and getting-to-know-you parties, clean-up drive, charity walk for typhoon victims, among others. The members are very accommodating and kind.