I don't think so - it's tied to SHA1 presently and would require updates to multiple plugins. I mean for your own DAV-style repository you could ALSO publish SHA256s, but there's no verification cycle as deps are pulled into a build client-side that'd use them.
- Maven artifacts SHA256 | SHA512 checksums Petr Ivanov
- Re: Maven artifacts SHA256 | SHA512 checksums Paul Hammant
- Re: Maven artifacts SHA256 | SHA512 checksums Elliotte Rusty Harold
- Re: Maven artifacts SHA256 | SHA512 checksums Konrad Windszus