Boston-based Fintech startup Stackwell has closed a $3.5M seed funding round led by three figures with Massachusetts ties: the Kraft Group, Fenway Sports Group President Mike Gordon and WS Development President Jeremy Sclar. Others joining the investment round include Red Sox CEO Sam Kennedy and MLB executive Theo Epstein, as well as SSC Venture Partners and the CMFG Ventures Discovery Fund. Stackwell, founded by CEO Trevor Rozier-Byrd, has plans to launch investing tools for the Black community intended to lower the barriers to entry and, ultimately, help close racial wealth gaps. Its first product, a robo-investing app, is expected to launch later this year.