I recently migrated from GnuCash to KMyMoney. While the latter is in general much more capable in all important to me aspects, one deficiency is that there is no possibility to make transfers between Expense accounts.

Specifically, I used to use a "Cash in Wallet" cash account to track my cash withdrawals. However, I found it very tedious to track all of the small expenses using regular, so I instead moved it to Expenses and did my best to track most of them (by transferring from Expense:Pocket Money to e.g. Expense:Food), leaving the rest as miscellaneous pocket money expense. It was also very easy to categorize a bigger expense retroactively, should I happen to have recalled one at a later time.

This worked perfectly, but is impossible to achieve in KMyMoney and I totally don't understand why.

To workaround it, I figured I could add the Asset:Cash in Wallet again and schedule automated transfers from it at the end of each month, except there's no way to have it automatically transfer the complete balance, so there's an added manual step of having to go to account and type in the end of the month balance.

Does anyone know any better way to achieve similar functionality?

This is probably the best you could do with current KMyMoney versions.