Yes, you can assign multiple VAT rates and categories to a transaction in Soldo by splitting it into lines. Read more about that here: How can I split a transaction into multiple line items? Each line must be assigned a ‘Xero Category’ and a ‘Xero Tax Rate’ before the transaction can be exported to Xero. These will be available in Xero after the transaction has been exported.
Note: Other imported Xero lists, such as tracking codes, can only be applied to a transaction as a whole and not to a certain line.