Yes it is possible. In fact it is one of the 2 prime functions of the unit.

However the process is indirect as the Memory (6043) is not able to send Locomotive/decoder commands, it can be used only to switch accessories.

As well as the 6043 you would need ...
- a controller (602x)
- accessory decoders (6083x/6084x)
- - with electronic points / signals
- feedback detection (6088x) for automation
- programing capability (usually the 6040 keyboard, or interface)

Thus to stop a train you would utilize a signal with an accompanying dead section (track power turned off when signal aspect is red).

There is no timer function available so what is required is a looping sequence of "cause and effect" - one (moving) train triggers a sequence that starts another. The sequence usually also includes the setting of an appropriate route.

Using the dead section concept , trains do stop abruptly. An option to insert a slowdown circuit is possible, however the operation of this depends on the locomotive motor/decoder capabilities. The direction of travel also needs to be taken into account.
A side issue is that early decoders would only retain their memory ( of speed and direction) for a few seconds. As a result they would not start when the signal went green. A trick to provide a "trickle of power" to the dead section gets you around this.

If you think you have a 6043 lined up for a good price, I suggest you double-check the business case against a 605x(interface) utilizing a PC, or an investment towards a CS.
Either of which perform the same function but with a bit more flexibility and functionality.

For example a PC can add
- Locomotive commands
- - controlled slowdown
- - function activation (Lights, telex, sound ...)
- - reverse
- Timings (delays / auto start)
- Randomization
- Flexibility (e.g. a different number of trains in the fiddle yard)

All that said, if you have a fixed sequence in mind that you just wont to be able to turn power on and press go then the 6043 is the way to go