This KBA explains how to best set up a Language Adaptation.
SAP Cloud for Customer
In general it is OK to select multiple workcenters in one Language Adaptation, up to 20 is OK.
The recommendation is to split the LA's per Text Type rather than per Workcenter. Means: Create 4 LA's per target language (one for each text type) and select as many workcenters as you want.
If you run into a timeout due to the high amount of texts you may either split again into bunches of workcenters or use the asynchronous Collect Text (considering the warning given in the pop-up).
SAP Help Portal: Translate and Adapt User Interface Texts
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