Nothing has changed between Delphi 2007 and Delphi 10 Seattle that affects the function shown in the question in any way.
The common problems that arise when moving between pre-Unicode Delphi, and Unicode Delphi, relate to differences in the treatment that character and string types. So,
Char was formerly an alias to
AnsiChar, but is now an alias to
WideChar. Likewise for
string etc. But that's not the case here. The types that you use have identical meaning on all Delphi versions from Delphi 2 upwards.
The error message is:
The procedure entry point _ThisIsFuncNameinFortran could not be located in dynamic link library.
There is only one way to interpret that error message. The DLL has been located, but it really does not export a function with that name. Check that the actual DLL loaded really is the one that you intended to load. Dependency Walker, or a similar tool, can probably help.