Can I mark some terms with a label within ONE Term Base? Yes. You can go into the term base and assign labels on term and concept level. From the Global Search interface, however, it is only possible to add labels on concept level.
Unfortunately I’m not quite qualified to give you a recommendation in this question. Different tools have different advantages so they always have to be put into the framework of the use case you have. A good first point for your research might be Nimdzi’s TBS Feature Explorer that lists the most common termbase systems on the market and lets you compare some features. No TBS on the market is natively compatible with Wordbee’s term manager if we are talking about APIs. Through Wordbee’s API it is technically possible to connect another cloud-based TBS to your Wordbee platform, however, there is no out of the box solution and development will only be covered in the framework of a paid custom development. …