It may work, it may not work.
Basically, for things to work you would need to:
- Have the same voltage.
- Be able to supply at least the same amperage.
- Have a correct connector (center pin negative vs center pin positive is not always obvious, but is a good way to release that magic smoke. So make sure polarity matches).
- Same kind of power (AC vs DC).
Your voltage is close but 4½ volts is still a full fifth less then 5 volts. That may be to much of a difference. Noone is going to guarantee that that will work without knowing much more about whatever it is you are trying to power.
Bottom line: Unless you do not care about replacing your HDMI splitter or the devices connected to it I would not try it.