francisp is correct that Husbzb-1 is the only compatible combo dongle available that supports both Zigbee and Z-Wave (and that the Z-Wave radio in Husbzb-1 is for North America only), but you also have to understand that the fact that there are no other combo dongles is not really a limitation, as if you think about it you will probably come to the conclusion that you do not want a combo adapter.
IMHO, best is to not have a combo stick. Ever heard the expression “Jack of all trades, master of none.”? The Husbzb-1 is not the best Zigbee dongle and it is not the best Z-Wave dongle, and for the same amount of money you can get a separate Zigbee and Z-Wave adapter dongles. Most would at least argue that it is better to separately have one dedicated adapter for Zigbee and one dedicated adapter for Z-Wave as it gives you most flexibility and easier upgrade paths. Regarding that it should be noted that the Husbzb-1 Zigbee have an older Zigbee chip inside it that is not very powerful and it is only compatible with ZHA in Home Assistant.
For Zigbee it depends if you plan on using ZHA, Zigbee2mqtt or DeCONZ. If you are on a budget then get an inexpensive Texas Instruments CC2531 dongle (preferably with an external antenna) as that is compatible with ZHA and Zigbee2mqtt, alternatively you could get a more expensive but much more powerful CC2652 dongle. If support for DeCONZ is your requirement then ConBee or ConBee II dongles is your only option, those are also compatible with ZHA and in development for Zigbee2mqtt but should be noted that they do not Zigbee 3.0 (however that is not yet an issue today). If you are sure that you will only use ZHA then a great new alternativly adapter is the Sonoff ZBBridge Zigbee-to-WiFi bridge as it is relativly inexpensive plus contains a very powerful radio and can now be hacked with a Tasmota firmware for ZHA compatibility.
For Z-Wave I currently recommend Aeon Z-Stick Gen5 for Z-Wave 500 series if money is no option (though next-generation Aeon Z-Stick for Z-Wave 700 series and other next-generation dongles is said to be ready for general release before the end of the year). On a budget, you can instead get the Z-Wave.Me UZB stick (which is also Gen5).