diff --git a/pm/workspace.py b/pm/workspace.py
index 5890c0e93c..435deddfc9 100644
--- a/pm/workspace.py
+++ b/pm/workspace.py
@@ -230,6 +230,14 @@ def _workspace_member(plugin_dir: Path, root: Path, *, identity: Path) -> Path:
         shutil.copytree(plugin_dir, member, symlinks=True,
                         ignore=_member_ignored)
         document = tomllib.loads(pyproject.read_text(encoding="utf-8-sig"))
+        # uv identifies a workspace member by [project].name, so the same virtual
+        # plugin enabled in two profiles would declare one name twice and fail
+        # `uv lock`. A member with no build backend is metadata-only: it can carry
+        # the unique key in its name, as manifest-only members already do. A
+        # buildable member keeps its declared name — uv verifies it against the
+        # package metadata its backend produces.
+        # tool.uv.package = true opts into uv package mode: real build metadata, so buildable.
+        virtual = "build-system" not in document and document.get("tool", {}).get("uv", {}).get("package") is not True
         changed = declaration.install_requirements != declaration.requirements
         if changed:
             document["project"]["dependencies"] = list(declaration.install_requirements)
@@ -245,7 +253,9 @@ def _workspace_member(plugin_dir: Path, root: Path, *, identity: Path) -> Path:
                     continue  # The referenced tree was copied with this member.
                 spec["path"] = (identity / relative).resolve().as_posix()
                 changed = True
-        if changed:
+        if virtual:
+            document.setdefault("project", {})["name"] = f"hermes-plugin-{key}"
+        if virtual or changed:
             import tomli_w
 
             (member / "pyproject.toml").write_text(tomli_w.dumps(document), encoding="utf-8")
diff --git a/tests/pm/test_environment_build.py b/tests/pm/test_environment_build.py
index 8780eaa17f..500b1292b6 100644
--- a/tests/pm/test_environment_build.py
+++ b/tests/pm/test_environment_build.py
@@ -677,7 +677,14 @@ def test_explicit_workspace_preserves_seed_and_replays_copied_members(locked_pro
     assert document["project"] == tomllib.loads(project.read_text(encoding="utf-8-sig"))["project"]
     [relative] = document["tool"]["uv"]["workspace"]["members"]
     copied = recorded / relative / "pyproject.toml"
-    assert copied.read_bytes() == before_member
+    copied_document = tomllib.loads(copied.read_text(encoding="utf-8-sig"))
+    expected = tomllib.loads(before_member.decode("utf-8"))
+    # A virtual member is renamed to its unique key (uv rejects two members with
+    # one [project].name); everything the plugin declared must survive verbatim.
+    assert copied_document["project"]["name"].startswith("hermes-plugin-member-")
+    del copied_document["project"]["name"]
+    del expected["project"]["name"]
+    assert copied_document == expected
     assert copied.resolve().is_relative_to(recorded.resolve())
     (original_member / "pyproject.toml").unlink()
     assert workspace.members_stamp([original_member]) != stamp
diff --git a/tests/pm/test_member_selection.py b/tests/pm/test_member_selection.py
index c1dd3d4aa1..e0230b0186 100644
--- a/tests/pm/test_member_selection.py
+++ b/tests/pm/test_member_selection.py
@@ -37,3 +37,53 @@ def test_manifest_only_member_is_named_after_its_plugin_dir_and_stays_unique(tmp
     assert all(name.startswith("hermes-plugin-my-plugin-") for name in names), names
     assert names[0] != names[1]
     assert members[0].name != members[1].name
+
+
+def test_pyproject_member_is_renamed_by_its_key_and_stays_unique(tmp_path):
+    """A plugin that ships its own pyproject declares its real [project].name, and
+    uv identifies workspace members by that name — enabling the plugin in two
+    profiles then fails ``uv lock`` with "Two workspace members are both named
+    …". Rename metadata-only members by their unique key, like manifest-only
+    ones; a buildable member keeps the name its package metadata reports."""
+    import tomllib
+    from pm.workspace import _workspace_member
+
+    members = []
+    for home in ("home-a", "home-b"):
+        plugin = tmp_path / home / "plugins" / "hindsight"
+        plugin.mkdir(parents=True)
+        (plugin / "pyproject.toml").write_text(
+            '[project]\nname = "hermes-plugin-hindsight"\nversion = "1.0.0"\n'
+            'dependencies = ["hindsight-client>=0.10.1"]\n',
+            encoding="utf-8",
+        )
+        root = tmp_path / f"gen-{home}"
+        root.mkdir()
+        members.append(_workspace_member(plugin, root, identity=plugin))
+    names = [tomllib.loads((m / "pyproject.toml").read_text(encoding="utf-8"))["project"]["name"] for m in members]
+    assert all(name.startswith("hermes-plugin-hindsight-") for name in names), names
+    assert names[0] != names[1]
+    document = tomllib.loads((members[0] / "pyproject.toml").read_text(encoding="utf-8"))
+    assert document["project"]["version"] == "1.0.0"
+    assert document["project"]["dependencies"] == ["hindsight-client>=0.10.1"]
+
+
+def test_buildable_pyproject_member_keeps_its_declared_name(tmp_path):
+    """uv verifies a buildable member's [project].name against the package metadata
+    its backend produces, so renaming it breaks the build ("Package metadata name
+    … does not match given name"); only metadata-only members may be renamed."""
+    import tomllib
+    from pm.workspace import _workspace_member
+
+    plugin = tmp_path / "home" / "plugins" / "replay"
+    plugin.mkdir(parents=True)
+    (plugin / "pyproject.toml").write_text(
+        '[project]\nname = "replay-plugin"\nversion = "1.0"\n'
+        '[build-system]\nrequires = []\nbuild-backend = "backend"\n',
+        encoding="utf-8",
+    )
+    root = tmp_path / "gen"
+    root.mkdir()
+    member = _workspace_member(plugin, root, identity=plugin)
+    assert (member / "pyproject.toml").read_text(encoding="utf-8") == (
+        plugin / "pyproject.toml").read_text(encoding="utf-8")