My high effort, brute force method would be to dump private keys from web wallet install SmartCash full node client, enter dumped private keys and then do the above export/import wallet. If you are completely comfortable with this then have at it. Moving your old crypto out of the old wallet beforehand lowers risk but you re-incur the 30-day smartrewards wait. I'm familiar with HD wallets and seed phrases, but not SmartCash's. So, I would not know the HD method, if any.
The method I would really try is dump private keys from web wallet, install SwiftCash 1.0.0 wallet (I'm Windows), enter private keys into new wallet. Again, if you're totally comfortable with all this go for it.
Otherwise, avoid any of my suggestions and wait for the SMEs to respond. SMEs if you want me to document the process let me know with edits please. I just don't want to build doc for an inaccurate or incomplete process.