I'm not familiar with it, but it sounds like it advises Congress as well as the President.

https://en.wikipedia.org/wiki/National_Science_Board

The National Science Board (NSB) of the United States establishes the policies of the National Science Foundation (NSF) within the framework of applicable national policies set forth by the president and Congress. The NSB also serves as an independent policy advisory body to the president and Congress on science and engineering research and education issues.

As an independent federal agency, NSF does not fall within a cabinet department. Rather, NSF's activities are guided by the National Science Board. The Board was established by Congress to serve as a national science policy body and to oversee and guide NSF's activities. It has dual responsibilities to: a) provide independent national science policy advice to the president and the Congress; and b) establish policies for NSF.

While most of the government is under the Executive Branch, there are some institutions that are in the Legislative Branch, like the Congressional Research Service:

https://en.wikipedia.org/wiki/Congressional_Research_Service

The Congressional Research Service (CRS) is a nonpartisan public policy research institute under the Library of Congress of the United States Congress. CRS works primarily and directly for members of Congress and their committees and staff on a confidential, nonpartisan basis. CRS is sometimes known as Congress's think tank due to its broad mandate of providing research and analysis on all matters relevant to national policymaking.[3]

CRS is one of three major legislative agencies that support Congress, along with the Congressional Budget Office (which provides Congress with budget-related information, reports on fiscal, budgetary, and programmatic issues, and analyses of budget policy options, costs, and effects) and the Government Accountability Office (which assists Congress in reviewing and monitoring the activities of government by conducting independent audits, investigations, and evaluations of federal programs). Collectively, the three agencies employ more than 4,000 people.[4]

I'm pretty sure that Trump doesn't have authority over the CRS.

I suppose that there will probably be some lawyers opining on it, though given that it's seven people, they may not bother challenging it.