Even though there is a problem with mongodb-stitch-browser-sdk, if you dig through the Closure output for this module, you can see that it exports core as well as mongodb-stitch-browser-services-mongodb-remote which you seem to be able to access:
$ clj -m cljs.main -co co.edn -d out -r
ClojureScript 1.10.339
cljs.user=> (require '[mongodb-stitch-browser-core :as core])
cljs.user=> core/StitchClientErrorCode
#js {"0" "LoggedOutDuringRequest", "1" "MustAuthenticateFirst", "2" "UserNoLongerValid", "3" "CouldNotLoadPersistedAuthInfo", "4" "CouldNotPersistAuthInfo", :LoggedOutDuringRequest 0, :MustAuthenticateFirst 1, :UserNoLongerValid 2, :CouldNotLoadPersistedAuthInfo 3, :CouldNotPersistAuthInfo 4}
cljs.user=> (require '[mongodb-stitch-browser-sdk :as stitch])
cljs.user=> stitch
ReferenceError: Can't find variable: module$private$tmp$npm_deps$node_modules$mongodb_stitch_browser_sdk$dist$esm$index
cljs.user=> (require '[mongodb-stitch-browser-services-mongodb-remote :as remote])
cljs.user=> remote
#js {:RemoteInsertManyResult #object[RemoteInsertManyResult], :RemoteMongoReadOperation #object[RemoteMongoReadOperation], :RemoteMongoClient #js {:factory #object[class_1 [object Object]]}}