open street map

My question is know if it is possible use open street map in plugin geolocation

You can do this if you have some JavaScript (and maybe also PHP) skills. Basically, you'd use the plugin only to collect and store the location data and then use some other method for displaying the map on the front end.

Location data
You could use the KML file created by the plugin (which is at yoursite/geolocation/map.kml) or create your own array of locations using PHP (e.g. via a theme function in custom.php or by writing a plugin that just outputs the data you need in, say, a simplified JSON feed).

Map display
Then you can use Javascript in your theme to generate whatever kind of map you need, maybe using a library like LeafletJS (for KML, you'll need a plugin).

It's not exactly an easy solution but...