This is entirely unnecessary. Once the credit card has been set up as a cash account, as described in the linked Guide above, use the Transfer Money feature between the two accounts. No other temporary or clearing account is necessary. The fact that the two cash accounts involved (the credit card and some other bank account) may be at different institutions is immaterial. If they are, fine; you may be able to pay the credit card by a direct, internal transfer. If not, write a check; the Transfer Money function allows you to show both in incoming and outgoing halves of the transfer as pending until the check clears.
As for using personal credit cards for corporate expenses, use Expense Claims. See the Guide below: