Tensho Office states that every room is fully private, individually air-conditioned and lockable — the physical characteristics the Business Manager Visa premises requirement is concerned with, since a partition that does not reach the ceiling will not do. It also states plainly that corporate registration is supported, which is a separate question from the visa but one founders need answered.
Published pricing starts at JPY 29,700 a month, among the lowest of any private-room operator we have seen, across locations in nine Tokyo wards plus five in Osaka. Two things it does not state: whether a formal lease agreement is issued (immigration will want to see one clearly for business use), and whether it offers English-language support. Both are worth asking before signing. The site mentions short-term contracts, so confirm you can get the longer term an application generally expects.